初二升初三暑假作业参考答案

数学练习（一）8、如图3，在ABC △中，AC BC AB =>，点P 为ABC △所在平面内一点，且点P 与ABC △的任意两个顶点构成△PAB 、△PBC 、 △PAC 均是．．等腰三角形，则满足上述条件的所有点P 的个数为（ ▲ ） A ．3B ．4C ．5D ．611、如图4，将直角边长为5cm 的等腰直角ΔABC 绕点A 逆时 针旋转15° 后,得到ΔA B’C ’,则图中阴影部分的面积是 ▲ cm 213、一个叫巴尔末的中学教师成功地从光谱数据 95 ，1612 ，2521 ，3632 ，… 中得到巴尔末公式，从而打开了光谱奥秘的大门，请你按照这种规律，写出第n （n ≥1）个数据是 ▲18、已知Rt △ABC 中，∠C=90º。

（1）根据要求作图（尺规作图，保留作图痕迹，不写画法） ①作∠BAC 的平分线AD 交BC 于D ；②作线段AD 的垂直平分线交AB 于E ，交AC 于F ，垂足为H ； ③连接ED 。

（2）在（1）的基础上写出一对相似比不为1的相似三角形和一对全等三角形： △________∽△________；△________≌△________。

22、已知反比例函xky =图象过第二象限内的点A （－2，m ）AB ⊥x 轴于B ，Rt △AOB 面积为3 （1）求k 和m 的值；（2）若直线y=ax+b 经过点A ，并且经过反比例函xk y =的图象上另一点C （n ，－23）①求直线y=ax+b 解析式；②设直线y=ax+b 与x 轴交于M ，求△AOC 的面积；C（图3）B A图4（18题图）CB（22题图）24、如图1，以矩形OABC 的两边OA 和OC 所在的直线为x 轴、y 轴建立平面直角坐标系，A 点的坐标为（3，0），C 点的坐标为（0，4）．将矩形OABC 绕O 点逆时针旋转，使B 点落在y 轴的正半轴上，旋转后的矩形为OA 1B 1C 1，，BC 、A 1B 1相交于点M ． （1）求点B 1的坐标与线段B 1C 的长；（2）将图1中的矩形OA 1B 1C 1，沿y 轴向上平移，如图2，矩形PA 2B 2C 2，是平移过程中的某一位置，BC 、A 2B 2相交于点M 1，点P 运动到C 点停止．设点P 运动的距离为m ，矩形PA 2B 2C 2，与原矩形OABC 重叠部分的面积为S ，求S 关于m 的函数关系式，并写出m 的取值范围； （3）如图3，当点P 运动到点C 时，平移后的矩形为PA 3B 3C 3，．请你思考如何通过图形变换使矩形PA 3B 3C 3，与原矩形OABC 重合，请简述你的做法．（24题图）Ａ ＯＣＢＭＡＯ ＣＢ1M ＡＯ Ｂ1B 1C 1A xyxyxy2B2CP2AＣ(Ｐ)3C 3B 3A 图1图2图3数学练习（一）参考答案8、D 11、 25 36 13、(n ＋2)2 (n ＋2)2－418、（1）根据要求作图（尺规作图，保留作图痕迹，不写画法）①作∠BAC 的平分线AD 交BC 于D 正确； …………2分②作线段AD 的垂直平分线交AB 于E ，交AC 于F ，垂足为H 正确； ……4分 ③连接ED 正确。

8升9模拟题（一）一、基础知识( 每小题 3 分)1．下列词语中加点字的注音，全都正确的一项是( )A．两栖（qī）解剖（pāo）气息奄奄（yàn）恃才放旷（shì）B．荒谬（miù）发酵（jiào）不屈不挠（náo）长吁短叹（yū）C．束缚（sù）拮据（jū）转弯抹角（mò）混淆是非（xiáo）D．庇护（bì）笨拙（zhuō）秩序井然（zhì）一模一样（mú）2．下列词语中没有错别字的一项是( )A．真缔造型花枝招展一拍即合 B．屏障琐屑销声匿迹姗姗来迟C．驰骋苍桑兴高采烈因地制宜 D．萧索安详大厅广众左右逢源3．下列句子中加点的成语使用不恰当的一项是( )A．高考前夕，江西高三学生柳艳兵和易政勇在公交车上被歹徒砍伤，见歹徒仍在行凶，他们义愤填．．．膺．，奋力夺刀，制止了歹徒，被网友称赞为“最美考生”。

B．2014年巴西世界杯足球赛正紧张激烈地进行着，上届夺冠失利的荷兰队卷土重来．．．．，在小组赛第一场大胜卫冕冠军西班牙队，再次向大力神杯发起冲击。

C．许多网友转载了《用微波炉烹调食物会致癌》的文章，专家指出，这种骇人听闻．．．．的传言没有科学依据，微波炉加热与常规加热对食物的影响基本相同。

D．近年来，新疆考古出土了多条裤子，其中一条距今已有1500年，不仅样式是当今时髦的灯笼裤型，而且用的还是现在仍流行的百褶布料，真是不可思议。

4．下列各句中没有语病的一项是（）A．中学生之所以喜欢网络文学作品的原因，是因为这些作品不仅表现手法自由活泼，而且思想感情丰富细腻。

B．有学者认为，央视“百家讲坛”栏目将国学经典通俗化，有利于更多人了解、研究传统文化。

C．近200年来，地球的森林已有三分之一左右被采伐和毁掉，尤其在近50年，部分地区森林减少了一倍。

D．我们要养成爱读书，特别是读经典，读名著，让书香飘满我们的生活。

第6题图7题图A ．B ．C ．D ． 数学练习（二）5．函数xk 1y -=的图象与直线x y =没有交点，那么k 的取值范围是 A ．1k > B ． 1k < C ．1k -> D ．1k -<6．如图，在△ABC 中，∠C =90°，若沿图中虚线剪去∠C ，则∠1＋∠2等于（ ） A ．315° B ．270° C ．180° D ．135° 7．我们从不同的方向观察同一物体时，可以看到不同的平面图形，由6个小正方体按如图所示的方式摆放，则这个图形的左视图是（ ）11．如图，从边长为a 的大正方形纸板中间挖去一个边长为b 的小正方形后，将其裁成四个相同的等腰梯形（如图甲），然后拼成一个平行四边形（如图乙）．那么通过计算阴影部分的面积可以验证我们学过的什么公式？答：_________ ．12．若多项式m x x +-2在有理数范围内能分解因式，把你发现字母m 的取值规律用含字母n （n 为正整数）的式子表示为 ．17．(本小题满分5分)如图，等腰直角△ABC 中，∠ABC=90°，点D 在AC 上，将△ABD 绕顶点B 沿顺时针方向旋转90°后得到△CBE.⑴求∠DCE 的度数；⑵当AB=4，AD ∶DC=1∶3时，求DE 的长.解：四、解答题（共2道小题，共10分）18．（本小题满分5分）如图，在梯形ABCD 中, AB//DC, ∠ADC=90︒, ∠ACD=30︒ ，∠ACB=45︒ ，BC=23，求AD 的长.解:11题图21（本小题满分6分）某公司投资某个工程项目，现在甲、乙两个工程队有能力承包这个项目．公司调查发现：乙队单独完成工程的时间是甲队的2倍，甲、乙两队合作完成工程需要20天；甲队每天的工作费用为1000元、乙队每天的工作费用为550元．根据以上信息，从节约资金的角度考虑，公司应选择哪个工程队、应付工程队费用多少元？解：六、解答题（本题满分4分）22．取一张矩形纸片进行折叠，具体操作过程如下：第一步：先把矩形ABCD对折，折痕为MN，如图1；第二步：再把B点叠在折痕线MN上，折痕为AE，点B在MN上的对应点为B'，得R t△A B'E，如图2；第三步：沿EB'线折叠得折痕EF，使A点落在EC的延长线上，如图3．利用展开图4探究：（1）△AEF是什么三角形?证明你的结论；（2）对于任一矩形，按照上述方法能否折出这种三角形?请说明你的理由．解：图1 图2图3 图4数学练习（二）参考答案11． 平方差公式； 12． ()1--=n n m17．解：（1）∵△CBE 是由△ABD 旋转得到的，∴△ABD ≌△CBE ，…………………………1分∴∠A ＝∠BCE ＝45°，∴∠DCE ＝∠DCB ＋∠BCE ＝90° …………………2分（2）在等腰直角三角形ABC 中，∵AB ＝4，∴AC ＝42.又∵AD ︰DC ＝１︰3，∴AD=2，DC=32.…………………………4分由（１）知AD ＝CE 且∠DCE ＝90°,∴DE 2＝DC 2＋CE 2＝2＋18＝20，∴DE ＝25.…………5分四、解答题（共2道小题，共10分）18．（本小题满分5分）解: 过点B 作BE ⊥AC 于E,则∠AEB=∠BEC= 90︒. ………1分∵ ∠ACB=45︒ ，BC=23，∴ 由勾股定理，得BE=EC=3. ………2分∵ AB//DC,∴ ∠BAE=∠ACD=30︒ . 又∵ AEBE = 30tan , ∴ AE=33. ………3分 ∴ AC=AE ＋EC=33+3. …………………4分在Rt △ADC 中,∠D=90︒, ∠ACD=30︒ ,∴ AD=.233321+=AC …………………………5分 21．解：设甲队单独完成需x 天，则乙队单独完成需要2x 天．……………1分 根据题意，得111220x x +=.…………3分 解得30x =．……………………4分 经检验30x =是原方程的解，且30x =，260x =都符合题意．∴应付甲队30100030000⨯=（元）．应付乙队30255033000⨯⨯=（元）．……………5分 ∴公司应选择甲工程队，应付工程总费用30000元．……………………………6分 六、解答题（本题满分4分）22．解：（1）△AEF 是等边三角形．由折叠过程可得：60BEA AEF FEC ∠=∠=∠=︒．∵BC ∥AD ，∴60AFE FEC ∠=∠=︒． ∴△AEF 是等边三角形．（2）不一定．当矩形的长恰好等于等边△AEF 的边AF 时，即矩形的宽∶长＝AB ∶AF ＝sin60°＝2:3时正好能折出． 如果设矩形的长为a ，宽为b ，可知当a b 23≤时，按此种方法一定能折叠出等边三角形； 当a b a ＜＜23时，按此法无法折出完整的等边三角形． 图 1 图2 图3 图4。

八年级到九年级暑期衔接Day 5一、根据汉语提示填写单词1. You can lift the box with a ________(手指) or two.2. Don't ________(扔) paper around the classroom.3. He doesn't have a sister and ________(也不) do I.4. Could I ________(借) your bike? Mine is broken.5. I like to sweep the floor, but I ________(讨厌) to do the dishes.二、语法填空阅读下面短文，在空白处填入一个适当的词，或填入括号中所给单词的正确形式。

Lin is a very kind girl. She is always ready to help people who are 6________ trouble. Now Lin is studying at the University of Texas. At the same time, she volunteers 7________ (teach) at Heart House in her free time. Heart House is a local after­school study program for children. It provides some extra 8________(educate) for children who are not doing 9________(good) in school.Lin goes to Heart House to teach the children 10________(two) a week. She also makes a website for Heart House. In this way, people will learn more 11________ Heart House and better help the children there. 12________(thank) to Lin's website, every week 125 volunteers spend two hours helping the children at Heart House now. “13________ Lin's website, Heart House would never be able to have enough volunteers，”the program leader said.“I feel happy to teach those kids 14_______ to study. I won't give up 15________(volunteer). I hope to continue teaching kids who need help，”Lin said.三、完形填空This is a true story. There was a player named Jerry in the football team. He liked playing __16__，but he wasn't good at it. So he had few chances to play for his team. He __17__ very sorry for it.One day, his father died from a terrible illness, he had to return to his __18__ to do something. After that, an important __19__ was going to begin. He found the coach at once and he asked the coach whether he could take part in the match or not. He was not good at skills, so the coach would not __20__ him to take part in the match at first. But now, as he relented(心软), he agreed to let Jerry play for only three __21__. When the time was up, he would be changed by others. On the court(球场), Jerry played very well. The coach was very pleased __22__ him. Three minutes __23__ the coach made Jerry keep staying on the court. Jerry kept on his __24__ performance(表现), leading the team to __25__ the match.The coach hugged him __26__ and said, “Kid, you have never been so fast, so strong and so skilled. What happened on earth(究竟)？” Jerry said, “There was something wrong with my father's eyes, __27__ he has never watched my match. Now, he's __28__ to the heaven and finally can watch my match. As soon as I think of my father watching me, I don't feel tired at all, and I feel __29__，too.”The coach understood: __30__ can drive everything. Do you agree with him?()16. A. football B. basketball C. tennis D. baseball()17. A. sounded B. smelt C. tasted D. felt()18. A. school B. home C. garden D. court()19. A. meeting B. activity C. match D. ceremony()20. A. order B. allow C. teach D. tell()21. A. minutes B. days C. hours D. seconds()22. A. in B. for C. with D. under()23. A. ago B. after C. before D. later()24. A. bright B. humorous C. proud D. excellent()25. A. win B. lose C. beat D. get()26. A. excitedly B. directly C. sadly D. gently()27. A. but B. or C. and D. so()28. A. been B. gone C. returned D. come()29. A. worried B. active C. hungry D. awful()30. A. Hobby B. Friendship C. Love D. Business四、阅读理解What does it feel like to break a bone(骨头)? It's different for everyone, but the pain is often serious. If the break is small, however, the person may feel little pain. If you think that you or someone else has broken a bone, the most important things to do are to stay calm, make the hurt person comfortable, and call the doctor. Do not move the hurt body part because movement could make it worse.To treat the break, the doctor will need to take an X­ray first. This gives the doctor the information that if he or she needs to set the bone. Then, put it back to its normal place. If the bone is large or it is broken in more than one place, the doctor may need to use metal pins(钢钉) to set it. After the bone has been set, the next step is usually putting on a cast, the special hard thing that will keep the bone in place for a month or two.Your bones are very good at becoming healthy themselves. Broken bones will make many new cells and tidy blood vessels(血管). These covers both end the broken part and close up the break until the bone is as whole and strong as before.()31. When someone breaks his bone, we shouldn't ________．A. stay calmB. ask the doctor for helpC. comfort the hurt personD. move the hurt part()32. According to Paragraph 2, the right order of treating the break is ________．a. take an X­rayb. use metal pins to set itc. put it back to its normal placed. put on a castA. a→c→b→dB. a→b→c→dC. a→d→c→bD. a→c→d→b()33. The best title for the passage would be ________．A. What Causes the Broken BonesB. What You Should Know About Broken BonesC. How to Know If a Bone Is BrokenD. How Broken Bones Become Healthy Themselves()34. We can most probably read the passage ________．A. in a storybookB. in a history bookC. in a health care bookD. in a geography book参考答案一、1. finger 2. throw 3. neither 4. borrow 5. hate二、6.in 7.to teach cation 9.well 10. twice11.about 12.Thanks 13.Without 14.how 15．volunteering三、16—20 ADBCB21—25 ACDDA26—30 ADBBC四、31—34 DABC。

初三化学暑假作业第一单元1．物理变化和化学变化的本质区别(也就是判断依据)是：变化时是否有新物质生成。

2．下列现象属于化学变化是__（1）（3）（4）（5）（10）(填序号)(1)铁生锈(2)石蜡熔化(3)纸张燃烧(4)食物腐烂(5)铜在潮湿的空气里生成铜绿(6)潮湿的衣服被晒干了(7)雪融化(8)向玻璃片哈气，会出现一层水雾。

(9)电灯发光(10)植物光合作用3．下列有关物质性质的描述中，属于物理性质是_（2）（3）（6）（9）（10）__(填序号)，(1)酒精能燃烧(2)浓盐酸能挥发(3)常压下，水的沸点是100℃(4)以粮食为原料能酿酒。

(5)二氧化碳能使澄清的石灰水变浑浊(6)空气是没有颜色、没有气味的气体(7)氧气具有助燃性(8)铁在潮湿的空气里易生锈(9)浓氨水具有挥发性(10)食盐易溶于水4．药品的取用(1) 固体药品通常保存在__广口瓶_里(2)液体药品通常盛放在__细口__瓶里，常用倾倒法取用。

倾倒液体药品操作要点：瓶塞_倒___放；标签___向着手心____；试剂瓶口__紧挨试管口。

(3) 用量筒量取液体读数时，视线要与凹液面的最低点保持水平(如果俯视时，读数高于实际数值；如果仰视时，读数低于实际数值)；4．检查装置的气密性（如右图）先_将右侧导管伸入水中__再__用水紧握试管__，如果水中的导管口有__气泡__冒出，说明装置不漏气。

5．把玻璃管插入带孔橡皮塞或连接玻璃管和胶皮管时，一般先把玻璃管口用__水___润湿，再连接。

6．洗涤玻璃仪器洗干净的标准：_内壁附着的水既不聚成水滴，也不成股流下_____第二单元 课题11．二百多年前，法国化学家__拉瓦锡___用定量的方法研究了空气的成分。

2．空气的成分按体积计算，大约是：氮气__78%___、氧气_21%__、稀有气体_0.94%__、二氧化碳___0.03%__、其他气体和杂质0.03％。

3．纯净物由_一_种物质组成；混合物由_两种或两种以上的物质混合而成的。

数学练习（四）5．若1x 、2x 是一元二次方程0572=+-x x 的两根，则2111x x +的值是（ ） （A ）57 B ）57- （C ）75 （D ）75- 6．某超市进了一批商品，每件进价为a 元，若要获利25%，则每件商品的零售价应定为（ ）（A ）a %25 （B ）()a %251- （C ）()a %251+ （D ）%251+acm ）。

将它们拼成如图2的新几何体，则该新几何体的体积为（ ）33．72πcm 3 D ．84πcm 312．估计215-与0.5的大小关系是：215-________0.5（填“>”、“=”、“<”）。

14．若不等式组⎩⎨⎧>->-022x b a x 的解集是11<<-x ，则=+2008)(b a ________。

图2图110. 将图（1）所示的正六边形实行分割得到图（2），再将图（2）里的三个小正六边形的其中之一按同样的方式实行分割得到图（3），接着再将图（3）中最小的三个正六边形的其中之一按同样的方式实行分割…，则第n 图形中共有 个六边形．（提示：可设y=an 2+bn+c,把代入求a,b,c.再求y=?）15．分别剪一些边长相同的①正三角形，②正方形，③正五边形，如果用其中一种正多边形镶嵌，能够镶嵌成一个平面图案的有……………………【 】 A.①② B.②③ C.①③ D.①②③都能够10．根据图中提供的信息，用含n （n ≥1，n 是正整数） 的等式表示第n 个正方形点阵中的规律是：_____.16. 如图所示，将边长为8cm 的正方形纸片ABCD 折叠，使点D 落在BC 中点E 处，点A 落在F 处，折痕为MN ，则线段CN 的 长是………（ ） A. 2 B. 3 C. 4D. 5⎩⎨⎧==⎩⎨⎧==⎩⎨⎧==73,42,11y n y n y n ……EDCBA8．若等腰△ABC 的底边和腰长分别是一元二次方程01582=+-x x 的两个根，则这个等腰三角形的周长是（ ）A ．11 B ．13 C ．11或13 D ．无法确定 13．如图，DE 是△ABC 的中位线，AB+AC=16cm ，DE=3cm ，则梯形DBCE 的周长为 ．23、（本题满分12分）如图，在直角梯形纸片ABCD 中，AB ∥DC ，︒=∠90A ，AD CD >，将纸片沿过点D 的直线折叠，使点A 落在边CD 上的点E 处，折痕为DF ．连接EF 并展开纸片．（1）求证：四边形ADEF 是正方形；（2）取线段AF 的中点G ，连接EG ，如果CD BG =，试说明四边形GBCE 是等腰梯形．24．如图，以O 为原点的直角坐标系中，A 点的坐标为（0，1），直线x =1交x 轴于点B ．P 为线段AB 上一动点，作直线PC ⊥PO ，交直线x =1于点C ．过P 点作直线MN 平行于x 轴，交y 轴于点M ，交直线x =1于点N ．（1）当点C 在第一象限时，求证：△OPM ≌△PCN ； （2）当点C 在第一象限时，设AP 长为m ，四边形POBC 的面积为S ，请求出S 与m 之间的函数关系式，并写出自变量m 的取值范围；（3）当点P 在线段AB 上移动时，点C 也随之ECBDAG F在直线x=1上移动，△PBC能否成为等腰三角形？如果可能，求出所有能使△PBC成为等腰三角形的点P的坐标；如果不可能，请说明理由．数学练习（四）参考答案5.C6.D 9.A 12.D 14．－2a 10、3n-2 15、A ； 18、C 18、C10、 . 15、C . 16、B. 8、C 13．17cm ．23、解：（1）∵△ADF ≌△EDF∴∠DEF=∠A=90°……………………1分 ∵AB ∥DC∴∠ADE=90°…………………………1分 ∴四边形ADEF 为矩形………………2分又∵DA=DE ∴ADEF 为正方形……………………2分 （2）过C 作CH ⊥AB ，垂足为H ……………………1分∵CE ∥BG ，CE≠BG ∴EGBC 是梯形……………………1分 ∵CH ⊥AB ∴∠CHA=90°又∵∠CDA=∠DAH=90° ∴ CDAH 为矩形 ∴CD=AH ………1分 又∵BG=CD ∴BG=AH ∴BH=AG 又∵AG=GF ∴GF=HB ………1分又∵∠EFG=∠CHB ，EF=CH ∴ △EFG ≌△CHB ……1分 ∴EG=CB ∴ EGBC 为等腰梯形……1分24．（1）证明：∵OM ∥BN ，MN ∥OB ，∠AOB=90°， ∴四边形OBNM 为矩形。

新课练13分子热运动一、单选题1.如图所示的各种现象中，能用来说明分子间存在引力的是（）A.0.5L水和0.5L酒精混合后体积小于1LB.煤堆放在墙角处多年后，墙角处变黑了C.将两铅块压紧后可悬挂物体，而两铅块不分开D.抽掉玻璃板后，两瓶中的气体混合了2.小明在学习“从粒子到宇宙”的知识后，有下列认识，其中正确的是（）A.扫地时灰尘飞舞能说明分子在做无规则运动B.海绵容易被压缩能说明分子间有空隙C.在探索比分子更小的微观粒子的历程中，卢瑟福首先发现了电子D.用扩散现象说明分子在运动是转换法的研究方法3.用分子的观点解释下列现象，不正确的是（）A.气体受热膨胀——气体分子间的距离变大B.走过花园，闻到花香——分子在不停地做热运动C.两块平整的玻璃不能压成一块玻璃——分子之间的斥力大于引力D.水和酒精混合后总体积变小——分子间有间隔4.世界卫生组织正式发布通告，将新型冠状病毒感染的肺炎将正式被命名为“2019冠状病毒病”（COVID-19），冠状病毒颗粒形状是球形的，直径非常小，可以在空气中悬浮很长一段时间，COVID-19病毒直径大概是（）A.0.1nmB.100nmC.0.1mmD.10mm5.机场安检过程中，防暴犬功不可没.即使隔着多层包装，防暴犬也能嗅出炸药的气味，这说明组成炸药的分子（）A.一直处于静止状态B.处于永不停息的运动中C.相互之间存在排斥力D.相互之间存在吸引力6.如图所示，在盛有冷水和热水的烧杯中各滴入一滴红墨水，观察到红墨水在热水杯中扩散的快.关于这一实验的目的，下列说法正确的是（）A.比较烧杯内水的内能大小B.比较两滴墨水的内能大小C.说明分子无规则运动的剧烈程度与温度有关D.说明热量可以从高温物体传递给低温物体7.二氧化氮气体的密度大于空气的密度，在装有红棕色二氧化氮气体的瓶子上面，倒扣一个空瓶子，使两个瓶口相对，之间用一块玻璃板隔开，如图所示。

抽掉玻璃板一段时间后，两种气体会在两个瓶子内均匀混合.针对上述现象，下列说法正确的是（）A.气体是由分子组成的B.气体分子间存在引力和斥力C.气体分子在做永不停息的无规则运动D.温度越高，气体分子无规则运动越剧烈8.对下列现象的解释，正确的是（）A.打开香水瓶盖后，能闻到香味，说明分子在永不停息地做无规则运动B.封闭在容器内的液体很难被压缩，说明分子间有引力C.用手捏海绵，海绵的体积变小了，说明分子间有间隙D.铅笔笔芯用了一段时间后会变短，说明分子间有斥力9.关于分子动理论。

数学练习（十三）7. 有一列数1a ，2a ，3a ，，n a ，从第二个数开始，每一个数都等于1与它前面那个数的倒数的差，若12a =，则2009a 为 A ．2009B ．2C ．21 D ．1-11．如图，P 为菱形ABCD 的对角线AC 上一点，AB PE ⊥于E ，AD PF ⊥于F ，3=PF ，则PE 的长是 .12．观察下列有序数对：)1,3(-，)21,5(-，)31,7(-，)41,9(-，…，根据你发现的规律，第100个有序数对是 ． 15．反比例函数xky =的图象在第一象限的分支上有一点A （2，3），P 为x 轴正半轴上的一个动点. （1）求反比例函数的解析式；（2）当P 在什么位置时，OPA ∆为直角三角形，求出此时P 点的坐标．22．如图，正方形网格中的每个小正方形的边长都是1，每个小格的顶点叫做格点．（1）在图１中以格点为顶点画一个面积为5的正方形；（2）在图２中以格点为顶点画一个三角形，使三角形三边长分别为3、4、5；（3）在图３中以格点为顶点画一个三角形，使三角形三边长分别为2、5、13．FEP D CBA第11题第22题图图１ 图2 图324．如图，在平面直角坐标系中，O 为坐标原点，AOB ∆为等边三角形，点A 的坐标是（34，0），点B 在第一象限，AC 是OAB ∠的平分线，并且与y 轴交于点E ，点M 为直线AC 上一个动点，把AOM ∆绕点A 顺时针旋转，使边AO 与边AB 重合，得到ABD ∆．（1）求直线OB 的解析式；（2）当M 与点E 重合时，求此时点D 的坐标；（3）是否存在点M ，使OMD ∆的面积等于33，若存在，求出点M 的坐标； 若不存在，请说明理由．25．（1）如图1，四边形ABCD 中，CB AB =，︒=∠60ABC ，︒=∠120ADC ，请你 猜想线段DA 、DC 之和与线段BD 的数量关系，并证明你的结论；（2）如图2，四边形ABCD 中，BC AB =，︒=∠60ABC ，若点P 为四边形ABCD 内一点，且︒=∠120APD ，请你猜想线段PA 、PD 、PC 之和与线段BD 的 数量关系，并证明你的结论．图2第25题第24题 CBA 0yxEO 图１数学练习（十三）参考答案7．C 11.3 12. )1001,201(- 15．解：（1）将)3,2(A 代入xky =， ……………………………………………1分 得 6=k ．所以函数解析式为xy 6=． ……………………………………………2分 （2）当︒=∠90OPA 时，)0,2(P ． ……………………………………………3分 当︒=∠90OAP 时，过A 作x AH ⊥轴于H ，由△OAH ∽△APH ， ……………………………………………4分得 PHAHAH OH =．即 292322===OH AH PH ． 所以，213292=+=OP ．此时，点P 的坐标为（213，0）． ……………………………………………5分 22．解：如图所示，每问1分，共3分．24．解：（1）B （32，6）；OB l ：x y 3=． ……………………2分（2）如图1，由题意x DA ⊥轴，︒=∠=∠30BAD EAO ．此时 823===OA AE DA ，即点D （34，8）． ……………………4分图1图 2 图3第22题ABCDExyOEE（3）如图2、图3，过M 作x MN ⊥轴，设a MN =，当M 在x 轴上方时，由︒=∠30OAM ，∴ a MA 2=，a NA 3=．=∆O M D S 33234213)2(21)334(21=⋅⋅-⋅++⋅-a a a a a a ． 解得3=a ．…5分 当M 在x 轴下方时，由︒=∠30NAM ，∴ a MA 2=，a NA 3=．=∆O M D S 33)334(213)2(2123421=⋅+-⋅++⋅⋅a a a a a a ． 解得1=a ．……6分 ∴ 1M （3，3），2M （35，1-）．………………7分 25．解：（1）如图１，延长CD 至E ，使DA DE =．可证明EAD ∆是等边三角形． ……………………………………………1分 联结AC ，可证明BAD ∆≌CAE ∆． ……………………………………………2分 故BD CE CD DE CD AD ==+=+．……………………………………………3分（2）如图２，在四边形ABCD 外侧作正三角形D B A '， 可证明C B A '∆≌ADB ∆，得DB C B ='．……………………………………………4分 ∵ 四边形DP B A '符合（1）中条件，∴ PD AP P B +='． ……………………………………………5分 联结C B '，ⅰ）若满足题中条件的点P 在C B '上， 则PC B P C B +'='． ∴ PC PD AP C B ++='．∴ PC PD PA BD ++= ． ……………………………………………6分 ⅱ）若满足题中条件的点P 不在C B '上，∵ PC B P C B +'<'，∴ PC PD AP C B ++<'．∴ PC PD PA BD ++<． ……………………………………………7分 综上，PC PD PA BD ++≤． ……………………………………………8分图 1图2第25题。

Day 1新目标英语暑假作业衔接教材（八升九）一、.根据句意及汉语提示完成句子1．I plan to send her some flowers as an ________ (表达方式) of thanks.2．English ________(语法) is boring, but it is important.So you must learn it well.3．It is a ________ (秘密) between you and me. Don't tell it to others.4．Could you tell me when Columbus ________ (发现) America?5．Try to guess the ________ (意思) of the word first.二、语法填空阅读下面短文，在空白处填入一个适当的词，或填入括号中所给单词的正确形式(每空不多于3个单词)。

Students learn their lessons in class. They sit in the classroom listening to their teachers. This is a way of 6.________(learn). Is this the only way 7.________ students to learn? Of course not. There is another way to learn. Students can teach 8.________(they). For example, if you cannot remember something 9.________ you are doing your homework, what will you do? You can look through your book to find the answer.10．________do you teach yourself? The first thing you should do is reading. Read something you are 11.________(interest) in, and you have to read. The12.________(two) is that you must ask yourself questions. A clever student is usually good at asking questions. The third is to answer the questions yourself by 13.________(work) hard, by reading books, and sometimes by asking other people. These are the ways of teaching yourself. If you keep doing 14.________these for a long time, you are sure 15.________(make) great progress in your study.三、.完形填空I'm enjoying my stay in Canada. It is my first experience of being abroad, and I am trying to __16__ as much as possible. Classes here are much more fun and very different from the classes in __17__. In China there are very few opportunities to practice __18__ and listening. Although many Chinese students have good __19__，their speaking is not good. Studying English at Fern is much more practical. We actually __20__ the language we are learning. I couldn't speak any English at all when I __21__ here. Thankfully, after about a month, things started getting __22__ and I made friends and started to settle in(适应). I am really __23__ to learn English here andFern is a very good language school.I have always wanted to have a sister. In my Canadian host family the__24__ has come true. __25__ the first day when I arrived, my host family welcomed me warmly. All the family members were __26__ and helpful, and they made me feel at home at once.My __27__，Joise, is very kind. She often explains their manners to me. Her mother explains ordinary things like housework. Together they __28__ me study and understand Canada. Joise told me a __29__. Last year, she met a Chinese student on a plane. She said she felt sorry because she did not say __30__ to the girl.I'm happy to live in Canada. I think it will be an important experience in my life.()16.A.travel B．learn C．think D．speak()17.A.Japan B．Canada C．China D．America()18.A.playing B．reading C．writing D．speaking()19.A.grammar B．writing C．English D．pronunciation ()20.A.write B．read C．hear D．use()21.A.stayed B．arrived C．returned D．left()22.A.harder B．worse C．busier D．easier()23.A.sad B．sorry C．happy D．afraid()24.A.fact B．truth C．dream D．advice()25.A.In B．For C．On D．During()26.A.serious B．friendly C．famous D．expensive ()27.A.sister B．father C．brother D．mother()28.A.want B．tell C．help D．order()29.A.joke B．project C．program D．story()30.A.everything B．anythingC．something D．nothing四、阅读理解Since 2018, the English listening and speaking test in Beijing has to be separated from the written one. And the listening and speaking test for all students who are taking senior high school entrance exams (中考) in Beijing is becoming more and more important. The test counts for 40 points in the whole English exam. During the 30-minute test, students have to fill in blanks,answer questions and retell stories after listening to different materials.The test is taken on a computer. They can take the test twice—once in December and again in March—to try to get a possible higher score.“It pushes us to speak. Though it was hard at the beginning, it's a good thing，” said Liu Haoxuan, from Beijing Dayu Middle School. He got a low score when he first took it last term. But he kept working hard in order to improve his pronunciation and other skills. He practiced speaking in front of a mirror every day. Later, he got a score of 39 in the test.Liu Tianyou, 14, from Beijing Yuying Middle School, has his own way to prepare for the spoken English test. He uses apps to take practice tests every day. “The apps will score your performance so that you can improve accordingly，” he said. “Also, the practice tests help me learn to take not es properly. They help me grasp topic sentences and key words.”()31.What do we know about the English listening and speaking test?A．Students have to take it twice a year.B．The test was introduced many years ago.C．It counts for 40 points in the whole English exam.D．Students can get high scores in the test easily.()32.What do students have to do in the test?a. Fill in blanks.b. Answer questions.c. Retell stories.d. Write stories.A．abc B．abdC．acd D．bcd()33.What do we learn from Liu Haoxuan's story?A．Practice makes perfect.B．Knowledge comes from questioning.C．Think twice before acting.D．Two heads are better than one.()34.What do we know about Liu Tianyou?A．He got a score of 39 in the test.B．He practiced for the test by using apps.C．He failed the English listening and speaking test.。

【实验器材】托盘天平（及砝码）、烧杯。 【设计实验】①在 100mL 烧杯中加入 30mL 稀硫酸铜溶液，将几根铁钉用砂纸打磨干净， 将盛有硫酸铜溶液的烧杯和铁钉一起放在托盘天平上称量，记录所称的质量 m1。 ②将铁钉浸到硫酸铜溶液中。待反应一段时间后溶液颜色改变时，将盛有硫酸铜溶液和铁 钉的烧杯放在托盘天平上称量，记录所称的质量 m2。比较反应前后的质量。
质量为 18，则 A 的相对分子质量为
A. 23
B. 46
C. 92
D. 96
5. 一定条件下，甲、乙、丙、丁四种物质在密闭容器中反应，测得反应前后各物质的质量
Байду номын сангаас
分数如图所示，下列说法正确的是
A. 丁是该反应的催化剂
B. 该反应的基本类型是分解反应
C. 反应前后原子的种类发生了改变 D. 该反应中乙、丙的质量比为 3：17
反应后各物质的总质量。（大于或等于或小于）
实验成功的关键：装置的气密性要良好；红磷
。
玻璃管下端与红磷接触的目的：点燃红磷。
气球的作用：
。
若用玻璃棒代替玻璃管：红磷燃烧放热，瓶内压强变大，橡皮塞被弹开或炸裂锥形瓶。 锥形瓶底部不铺上细沙的后果：红磷燃烧时放热使得锥形瓶瓶底炸裂。
二、探究实验——铁钉跟硫酸铜溶液反应前后质量的测定
新九年级化学暑期预习作业（十）
预习
第五单元 化学方程式 课题 1 质量守恒定律
一、探究实验——红磷燃烧前后质量的测定
【实验器材】托盘天平（及砝码）、锥形瓶、玻璃棒、气球
【设计实验】
① 在底部铺有细沙的锥形瓶中，放入一小堆干燥的红磷。
②在锥形瓶口的橡皮塞上安装一根玻璃管，在其上端系牢一个小气球，并使玻璃管下端能

初二英语暑假作业参考答案第一课时一. 1. magazines 2. honest 3. secret 4. believe 5. special6. appearance7. smiling8. solve9. correctly 10. pleasant二. 1. tall 2. willing 3. unhappy 4. humorous 5. really6. funny7. jokes8. feet9. pleased 10. the most carefully三. 1. to drink 2. laugh 3. to know 4. has sold 5. was given6. doesn’t rain, will go7. have , been8. has gone, would come9. travels 10. wants, finishes四. 1---5 C D C A D五. 1. Does, have, or 2. doesn’t wear 3. Why is 4. What is, like 5. keeps secrets六. 1. I don’t know much about this school.2. I miss my classmates in my old school.3. I just moved to Shanghai with my parents.4. My daughter is crazy about piano.5. I work in a new middle school.七. no field instead heavy really ever looked now means tiredness第二课时一. 1. generous 2. true 3. humor 4. advertisements 5. agree二. 1. cry 2. the coldest , the hottest 3. big, smaller 4. friendly 5. ours6. differences7. prettier8. more popular9. useful 10. more三. 1. found 2. aren’t 3. were watching 4. be taken 5. has taught6. to travel7. will be invited8. opening9. is raining 10. are sent四. 1---5 C C D C五. 1. slimmer than 2. What does , look like 3. taller any other4. What odes, want be5. what to do六. 1. This bridge is about 30 metres long.2. Make sure to finish the work before Friday.3. Linda is tall and slim, she looks really lovely.4. There are many places of interest in Beijing.5. The whole world is in front of me.七. 1. importance/ value eful/ valuable 3.Time4.lost /missing/ past5.leads/ contributes6.best第三课时一. 1. correctly 2. admire 3. practice 4. taste 5. even6. reader7. nervous8. encouragement9. wears 10. information二. 1. northern 2. unnecessary 3. polluted 4. widely 5. the most famous6. foggier7. arrival8. shaking9. the most popular 10. well, musical三. 1. shall, meet 2. am, won’t visit 3. lost, Did, see 4. Is , produced 5. have seen, arrived6. were playing7. closes8. was, lost9. Was, sent 10. were invited四. 1---5 B B C B B五. 1. older 2. less important 3. Is 4. the tallest , No one 5. How long does六. 1. He plans to do morning exercise every day.2. I feel uncomfortable during most of the trip.3. The Chinese team went to the final but didn’t win yesterday.4. It takes over an hour from the school to the World Park by underground.5. You can see the whole town from the top of the tower.七. 1---5 B A C D B 6---10 D C A D B第四课时一. 1. movies 2. languages 3. practise 4. popular 5. article6.shining7. beautiful8. harmless9. meaning 10. delightful二. 1. unhealthy 2. interesting 3. pleasant 4. more comfortable 5. helplesseful7. wonderful8. alone, lonely9. unhealthy 10. luckies7.三. 1. rises 2. were playing 3. will become 4. have been 5. taught6.How, found, found7. has gone8. Driving9. chatting 10. to spend四. 1-5 BACBA五. 1. too young to go out alone 2. take care of his mother at home 3. is too small for4.more beautiful5. her an imagination girl六. 1. different from my brother's 2. the same as that 3. the fewest points4.less time on his homework5. same size as mine七. 1-5 CCADA第五课时一. 1. hero 2. British 3. humorous 4. pop 5. dramas6.includes7. Tower8. skiing9. clapped 10. characters二. 1. the most important 2. boring 3. useless 4. endless 5. unpopular6.successfully7. watching8. unlucky9. silently 10. foggy三. 1. crying 2. took 3. have been 4. to see 5. hike6.visit7. Traveling8. has gone9. to go 10. twice四. 1-5 BBBCC五. 1. a Grade 7 student 2. when you are 16 years old 3. takes; a lot of time to collect stamps4. drives me to school5. to do六. 1. Spring is the best time to visit Chinese gardens. You must be very pleased.2.It is fantastic to have a bird's-eye view of HongKong.3.We screamed with excitement when the roller coaster were moving at high speed.4.The boy left his hometown when he was ten years old. He has been away for nearly 20 years.5.Mr Li went to Beijing for a meeting. He has been in Beijing for 3 days. He has been there three times.七. 1-5 CBAAB第六课时一．根据句意及所给的中文、英文解释、首字母写单词。

八年级到九年级暑期衔接Day 1一、根据句意及汉语提示写单词。

每空一词。

1.You can tell me about your (苦恼).Maybe I can give you some advice.2.On October 18,2019 in Zhejiang，a car (击) the fence and caused a big firebecause the driver was drunk.3.My sister is old enough to look after (她自己).4.My mother helped me move the heavy box (向) the desk.5.To my (惊奇)，Jane was a mother of two children.二、语法填空阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当的词或使用括号中词语的正确形式填空(每空不多于3个单词)。

If you don't keep 6________(you) warm enough, winter can be a time to have an illness. During the winter months, people 7________(easy) get colds and flu. Many people think they are the same, 8________ these two illnesses are different.Colds can stay with you for up to a week. You will have 9________ running nose, sore throat, headache, cough and fever. Flu is 10________(serious). You will feel sick very quickly. You will have a fever and a headache. Your body will hurt and become weak. This could last for up to four 11________(week)．Are there any ways to keep yourself away from colds or flu? Staying away from persons 12________ colds or flu may work. Try 13________(not touch) your nose or eyes if you have been close to someone who has a cold. Wash your hands, especially after 14________(clean) your nose. Going out with wet hair can also give you a cold!If you catch a cold or flu, go to bed and rest. Drink lots of water. Stay in a warm, well­aired(通风良好的) room. 15________ you have a headache, or your muscles(肌肉) hurt, don'tforget to take some medicine.三、完形填空Tian Haicheng is a farmer in a small village in Ningxia. He had a road __16__ in March 2016 and lost the use of his arms and __17__ in it. Two months later, his wife left, taking away their son. __18__，not everyone abandoned(抛弃) him. His daughter, Jiajia, stayed with him. And she had to __19__ him.__20__ Jiajia is only six years old, she has to do much work every day. She gets up at 6 a．m.and massages(按摩) Tian's arms and legs for half an hour. __21__ she goes to school, the little girl also brushes his teeth and washes his face.When Jiajia is at school, her grandparents, __22__ farmers, look after her father. After she comes back, Jiajia feeds Tian his dinner and helps him __23__ around the house using a DIY mobility device(移动装置)．Jiajia even shaves her father's beard(刮胡子). “__24__ the beginning, I didn't know __25__ to shave and I cut Dad's face and it bled，”she said. “But Dad said it didn't __26__. Now I'm very good at shaving. My grandmother says I shave it very clean.”After learning that some people make money through live streaming(直播), Tian __27__ live streaming for the first time in May 2017. Now he is __28__ and has more than 450，000 fans. “I'm happy living with my daughter and __29__. I hope Jiajia never __30__ studying. I plan to save some money to send Jiajia to college in the future，”he said.()16.A．accident B．invitation C．apartment D．decision()17.A.eyes B．ears C．legs D．stomach()18.A.Together B．Luckily C．Pretty D．Hardly()19.A.look for B．look at C．look after D．look like()20.A.Unless B．However C．Because D．Although()21.A.Before B．After C．When D．During()22.A.none B．both C．either D．each()23.A.move B．show C．wait D．build()24.A.Of B．On C．To D．In()25.A.what B．who C．why D．how()26.A.hit B．hurt C．risk D．control()27.A.tried B．replied C．stopped D．added()28.A.unlucky B．dangerous C．difficult D．successful()29.A.sons B．brothersC．parents D．grandparents()30.A.gets into B．gets off C．gives away D．gives up四、阅读理解On May 25th, 2016, Yang Jiang left us forever. Many people may know herbecause she is the wife of a famous writer, Qian Zhongshu. But in fact, she isalso a writer, a translator and also did many researches on foreign literature.Such two great writers fell in love with each other as soon as they met in Qinghua University. Then they married and gave birth to a daughter.Yang was born on July 17th, 1911. We can call Yang “sir”. In China, not only can a man be called “sir”，but also a woman if she is knowledgeable enough. Yang did a good job in writing. She wrote her own book SixChaptersfromMyLifeDo w nunder. In the book, she described the hardest life between her husband and her in a humorous way. Then she wrote another book SoontoHa v eTea. In 1988, she published her only novel Baptism. This book had some connection with her husband's famous work FortressBesieged. At the age of 96, she surprised the world with her last work ReachingtheBrinkofLife.Besides writing in Chinese, Yang was also good at English, French and Spanish. She made great contributions to Chinese literature with her translations. Yang famously translated DonQuixote from Spanish to Chinese, and it has been the most popular translation ever since.()31. Yang Jiang died when she was ________．A. 100 years oldB. 103 years oldC. 105 years oldD. 110 years old()32. Yang's book ________ is about her and her husband's life.A. BaptismB. SoontoHa v eTeaC. ReachingtheBrinkofLifeD. SixChaptersfromMyLifeDo w nunder()33. We can learn from the passage that Yang could speak at least ________ languages.A. twoB. threeC. fourD. five()34. According to the passage, which of the following is TRUE?A. In China, we only call a man “sir”.B. In 2007, Yang wrote her last book.C. Yang met her husband in Beijing University.D. Yang published lots of novels and translated many books.参考答案一、1. trouble 2. hit 3. herself 4. onto 5. surprise二、6. yourself7. easily8. but9. a10. more serious 11. weeks12. with13. not to touch14. cleaning15.If三、16－20.ACBCD 21－25.ABADD 26－30.BADCD四、31—34 CDCB。

八年级到九年级暑期衔接Day 3一、用方框中所给单词的适当形式填空we blood die spirit decide1. He lost lots of ________ in the accident.2. We should have the ________ of keeping doing things.3. The flood which happened last week caused 100 people's ________．4. We built the house ________. Nobody helped us.5. We are teenagers, so it's time for us to make our own ________．二、语法填空阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当的词或使用括号中词语的正确形式填空(每空不多于3个单词)。

Today, a lot of people are often 6________(worry) about getting good jobs to make much money. When they are free, they always think about doing for fun. 7________，few people think about what they can do to help others. In their opinion, they are 8________(lucky) than many people. So they think 9________ meaningful to spend time helping these people, like 10________(raise) money for homeless people and visiting children in the hospital. They think helping others is helping 11________(they). Maybe these things are simple ones, but they will make a big 12________(different) to people's future life. Since many years ago, many Chinese volunteers have moved to another place to do social work for 13________(year) and show their 14________(kind)．15________(make) our world more beautiful, everyone should play a part in helping others. Do you think so?三、完形填空Rebecca Schofield was diagnosed with cancer(诊断得了癌症) two years ago. __16__ she was treated for many times in hospital, she thought she was getting __17__ day by day. But a few months ago the things became worse. When Rebecca __18__ that she had only three months to live, the 17­year­old girl __19__ Canada decided to make a mark(标记) on the world while she still could: A mark of kindness(善行)．__20__ Rebecca made a bucket list(人生目标清单). Her list __21__ all the things from playing computer games to traveling abroad. But her most meaningful wish doesn't have __22__ to do with herself. Rebecca wants to __23__ people to do acts(行为) of kindness in her name before she leaves the __24__．“No matter who you are, if you see this __25__，please do an act of kindness for someone else.”Rebecca posted it on her Facebook. “It doesn't matter how big or small __26__ act is as long as you do something. Give money to the __27__ or even just wash the dishes without your parents' asking.”Rebecca's story has touched the __28__ of people from all over the world. Now thousands of people have __29__ their acts of kindness online in her name, from buying coffee __30__ a stranger to giving a Teddy Bear to a children's hospital.If you would like to help Rebecca, please start doing small acts of kindness by yourself.()16. A. After B. While C. Since D. Before()17. A. better B. sadder C. fatter D. angrier()18. A. showed B. learned C. forgot D. reported()19. A. to B. from C. around D. outside()20. A. Probably B. Luckily C. Especially D. Immediately()21. A. invents B. explains C. includes D. discovers()22. A. nothing B. anything C. something D. everything()23. A. allow B. offer C. refuse D. encourage()24. A. world B. house C. school D. hospital()25. A. game B. lesson C. message D. picture()26. A. my B. her C. his D. your()27. A. new B. poor C. strong D. healthy()28. A. arms B. heads C. hearts D. bodies()29. A. brought B. found C. shared D. finished()30. A. as B. for C. with D. like四、阅读理解Winston Churchill once said, “There's something about the outside of a horse that's good for the inside of a man.” Many health experts agree. For that reason, horses are used to treat(治疗) people, especially children with problems.Through the years, couple John and Monique Black had met many kids who needed help. Monique had had a history with horses and with young people. John had worked with children in trouble.Because of Monique's difficult childhood, she knew that horses could bring a hand. For years, Monique had dreamed of working with “broken horses and hurting children together”. Then in 2010, the Blacks founded Mercy Spring Ranch(MSR) in California.At the Ranch(农场)Children between the ages of 6 and 18 can join the program. The kids do ranch tasks and enjoy riding lessons and other activities. The goal is to teach life skills and to produce confidence and trust(信任) in the kids.Why horses?One expert says that horses can make people calm down(镇定). Mercy Ranch's results have been amazing! Some children who are easy to fight with others have become calmer after staying with the horses.When a horse feels safe, it will follow its leader. A child turns to believe in himself as he sees his achievements. Kids find that the skills needed with horses also help them in their real life.Children and family members agree with the program. And many say it changed their lives!One said, “They take you in with a smile and an open heart.”Another called it “a safe place of help and hope”．“I don't know where I'd be without the help of the horses，”said one boy.And finally someone mentioned, “Who_would_have_known_a_horse_could_teach_so_much！”()31. From the passage, we know that the Blacks ________．A. are health expertsB. help the children with problemsC. are brother and sisterD. were difficult in their childhood()32. According to the passage, we know that ________ can join the program.A. those who are good with horsesB. people easily out of controlC. kids who are horse loversD. children from six to eighteen()33. The reason why horses can treat people is that ________．A. horses make people calm downB. horses keep children busy all the timeC. children make horses feel safeD. children become the leaders of horses()34. The underlined sentence “Who would have known a horse could teach so much！”means that ________．A. nobody knew what a horse could doB. people were not sure if a horse worked wellC. it's amazing a horse could help hurting children so muchD. we didn't know the horses could teach children to jump()35. We learn from the passage that the program “Mercy Spring Ranch” is ________．A. freeB. expensiveC. strictD. helpful参考答案一、1. blood 2. spirit 3. death 4. ourselves 5. decisions二、6. worried7. However8. luckier9. it's 10. raising11. themselves12. difference13. years14. kindness15. To make三、16—20 AABBD21—25 CBDAC26—30 DBCCB四、31—35 BDACD。

新年的愿望作文新年的愿望作文450字（精选21篇）在学习、工作乃至生活中，说到作文，大家肯定都不陌生吧，写作文可以锻炼我们的独处习惯，让自己的心静下来，思考自己未来的方向。

相信许多人会觉得作文很难写吧，以下是小编帮大家整理的新年的愿望作文450字，欢迎阅读，希望大家能够喜欢。

新年的愿望作文篇1很快的二零一五年已经过了，新的一年也到来，新的学期也已经开始了，代表着必须把旧的一年的不愉快及不好的事情都抛开，把好的事情，值得高兴的事情都记起来。

当然啰！新的一年有新的期望和愿望：首先我第一个期望当然是希望我们全家能够身体健康、每一天都能过的平安、顺利。

再来当然是我的课业啰！我期望我自己在新的学期能够认真且虚心的询问老师不会的问题且务必全部都懂，我觉得我五上的时候还不够认真，所以五下我的成绩一定要突飞猛进，这样才不会辜负老师和家人的期望。

在最后，就是能在见到我之前的好同学，因为她转学了让我很伤心，所以我只要再看到她，我就心满意足了。

但是，不管有多少的希望和期望，都是要靠自己努力才能完成，因为天下没有不劳而获的事，要有好的成绩必须靠自己一点一滴的养成，把握当下的时间，好好充实自我，才不会白白浪费，毕竟，人的一生当中也没有太多的明天，聪明的我定会善加利用零碎的时间充实自己，以便达成我心中的目标。

新年的愿望作文篇2“五！四！三！二！一！新年快乐！咚——咚——！”随着爆竹的声响，新的一年向我们走来。

我有好多个愿望，多么希望在新的一年能实现。

我的第一个愿望是希望家人身体健康，因为我的姥姥长期身体不好，一年的药费都高过我的学费，而且还要帮忙带我的小表弟，我的舅舅还经常惹生气，生气对身体又不好。

还有，我爸爸喉咙经常有痰，也要买很多药，健康是福，愿全家人新的一年健健康康。

我的第二个愿望是希望我和同学们的成绩步步高升。

我的成绩中游，平常考试拿分不算高，但是每当期末考试都会名列前茅。

我想把平时成绩提高点，让我每次都有好成绩。

数学练习（十二）7．一幅美丽的图案，在某个顶点处由三个边长相等的正多边形密铺而成，其中有两个正八边形，那么另一个是A ．正三角形B ．正方形C ．正五边形D ．正六边形11．观察下列等式：122=，224=，328=，4216=，5232=，6264=，72128=，……．通过观察，用你所发现的规律确定20092的个位数字是 ． 18．已知反比例函数)0m (xmy 1≠=的图像经过点A )1,2(-，正比例函数x y 2=的图像平移后经过点A ，且与反比例函数的图像相交于另一点B (n,2)．（1）分别求出反比例函数和平移后的一次函数解析式； （2）求点B 的坐标；（3）根据图像写出使反比例函数的值大于一次函数的值的x 的取值范围．21．已知：如图，在梯形ABCD 中，AD ∥BC ，∠A=90o,BC=DC ，CF 平分∠BCD ，DF ∥AB .（1）求证：ΔBFC ≌ΔDFC ；（2）若∠BCD=60°，BC=8，求BE 的长.22．如图，在平面直角坐标系中，图形①与②关于点P 成中心对称.(1)画出对称中心P ，并写出点P 的坐标；(2)将图形②向下平移4个单位，画出平移后的图形③，并判断图形③与图形①的位置关系.(直接写出结果)解：（1）P （ ）（2）图形③与图形①的位置关系是 .EFA DBC(F)P BC A L 23．已知，关于x 的一元二次方程03a x )4a (x 2=+---)0a (<． （1）求证：方程一定有两个不相等的实数根；（2）设方程的两个实数根分别为21x ,x （其中21x x <），若y 是关于a 的函数，且12x 32x y +=，求这个函数的解析式；（3）在（2）的条件下，利用函数图像， 求关于a 的方程01a y =++的解．25．如图1，ABC △的边BC 在直线l 上，AC BC ⊥，且AC BC =；EFP △的边FP 也在直线l 上，边EF 与边AC 重合，且EF FP =． （1）在图1中，请你通过观察、测量，猜想并写出AB 与AP 所满足的数量关系和位置关系；（2）将EFP △沿直线l 向左平移到图2的位置时，EP 交 AC 于点Q ，连结AP ，BQ ．猜想并写出BQ 与AP 所满足 图1的数量关系和位置关系，请证明你的猜想；（3）将EFP △沿直线l 向左平移到图3的位置时，EP 的延长线交AC 的延长线于点Q ，连结AP ，BQ ．你认为（2）中所猜想的BQ 与AP 的数量关系和位置关系还成立吗？若成立， 图2 给出证明；若不成立，请说明理由．1 2 3 44 3 2 1ay O -1 -2 -3 -4 -4-3 -2 -1E BA CP LQFLF Q (E)PEBCA数学练习（十二）参考答案7．B 11．2,18．解：（1）∵反比例函数)0m (xmy 1≠=的图像经过点A )1,2(-， ∴2m -=． ……………………………………………………………….…1分 ∴x2y 1-= …………………………………………………………………..2分 设平移后的一次函数解析式为b x y +=， ∵一次函数的图像经过点A ， ∴b 21+-=，即3b =．∴所求一次函数的解析式为3x y += ………………………………………3分（2）∵一次函数的图像 经过B (n,2)，（也可由反比例函数解析式求n ） ∴23n =+，即1n -=．∴)2,1(B - ……………………………………………………………..….4分 （3）根据图像可知，当0x 12x <<--<或时，反比例函数的值大于一次函数的值．………………..5分 21．（1）证明：∵CF 平分∠BCD, ∴∠1=∠2. ∵BC=DC ，FC=FC,∴ΔBFC ≌ΔDFC . ……………………………………2分 （2）解：延长DF 交BC 于G. ∵AD ∥BC ，DF ∥AB ，∠A=90°, ∴四边形ABGD 是矩形.∴∠BGD=90°………………………………………………………………………………3分. ∵ΔBFC ≌ΔDFC, ∴∠3=∠4. ∵∠BFG=∠DFE,∴∠BGD=∠DEF=90°. ………………………………4分 ∵∠BCD=60°，BC=8,∴BE=BC oSin60⋅=34……………………………….5分22．4321GEFA DB C解：（1）画点P ， ········································· 1分 (15)P ，； ······················································· 2分 （2）画图形③， ··········································· 3分 图形③与图形①关于点(13)Q ，成中心对称． ········· 4分 23．解：（1）△=)3a (4)4a (2-+-=44a a2+-=2)2a (-∵a<0， ∴0)2a (2>-．∴方程一定有两个不相等的实数根． ·································································· 2分（2）2)2a ()4a (x 2-±-= =2)2a ()4a (-±-∴3a x -=或122a 4a x -=+--=． ………………………………………3分∵a<0，21x x <，∴1x ,3a x 21-=-= ……………………………………4分 ∴12x 32x y +==a23a 32-=-+-)0a (<…………………5分 （3）如图，在同一平面直角坐标系中分别画出a2y -= )0a (<和1a y --=)0a (<的图像．………………..6分由图像可得当a<0时，方程方程01a y =++的解是2a -=．………………………….7分 25．（本题8分）解：（1）AB AP =；AB AP ⊥．………………………………………………………2分 （2）BQ AP =；BQ AP ⊥．………………………………………………………….3分 证明：①由已知，得EF FP =，EF FP ⊥，45EPF ∴∠=． 又AC BC ⊥，45CQP CPQ ∴∠=∠=．CQ CP ∴=．在Rt BCQ △和Rt ACP △中，BC AC =，90BCQ ACP ∠=∠=，CQ CP =，Rt Rt BCQ ACP ∴△≌△，BQ AP ∴=．………………………………………………4分②如图2，延长BQ 交AP 于点M ．①②xyO 1 1QP ③lAB FC Q图2M12 34EPRt Rt BCQ ACP △≌△，12∴∠=∠．在Rt BCQ △中，1390∠+∠=，又34∠=∠，241390∴∠+∠=∠+∠=．90QMA ∴∠=．BQ AP ∴⊥．………………………5分（3）成立． 证明：①如图3，45EPF ∠=，45CPQ ∴∠=．又AC BC ⊥，45CQP CPQ ∴∠=∠=．CQ CP ∴=．…………………………6分在Rt BCQ △和Rt ACP △中，BC AC =，90BCQ ACP ∠=∠=，CQ CP =，Rt Rt BCQ ACP ∴△≌△．BQ AP ∴=．……………………………………………7分②如图3，延长QB 交AP 于点N ，则PBN CBQ ∠=∠．Rt Rt BCQ ACP △≌△，BQC APC ∴∠=∠．在Rt BCQ △中，90BQC CBQ ∠+∠=，90APC PBN ∴∠+∠=．90PNB ∴∠=．QB AP ∴⊥．…………………………………………………………………………………..8分lABQP EF图3N C。

FEDCB A数学练习（十一）12．填在下面三个田字格内的数有相同的规律，根据此规律，请填出图4中的数字.5675320531108975图1 图2 图3 图48．水以恒速（即单位时间内注入水的体积相同）向一个容器注水，最后把容器注满，在注水过程中，水面高度h 随时间t 的变化规律如图所示（图中OABC 为一折线)，这个容器的形状是图中20． 在2008年春运期间，我国南方出现大范围冰雪灾害，导致某地电路断电，该地供电局组织电工进行抢修。

供电局距离抢修工地15千米，抢修车装载着所需材料先从供电局出发，15分钟后，电工乘吉普车从同一地点出发，结果他们同时到达抢修工地。

已知吉普车速度是抢修车速度的1.5倍，求这两种车的速度.21．（本小题满分5分）将直线1y x =+向左平移2个单位后得到直线l ，若直线l 与反比例函数ky x=的图象的交点为（2，-m ）．（1）求直线l 的解析式及直线l 与两坐标轴的交点； （2）求反比例函数的解析式．25.(1)如图25-1，在四边形ABCD 中，AB ＝AD ，∠B＝∠D ＝90°，E 、F 分别是边BC 、CD 上的点，且∠EAF=12∠BAD.求证:EF ＝BE ＋FD;A B C DABCO th(2) 如图25-2在四边形ABCD 中，AB ＝AD ， ∠B+∠D ＝180°，E 、F 分别是边BC 、CD 上的点，且∠EAF=12∠BAD, (1)中的结论是否仍然成立？不用证明.(3) 如图25-3在四边形ABCD 中，AB ＝AD ，∠B+∠ADC ＝180°，E 、F 分别是边BC 、CD 延长线上的点，且∠EAF=12∠BAD, (1)中的结论是否仍然成立？若成立，请证明；若不成立，请写出它们之间的数量关系，并证明.22．（本小题满分5分）已知： 如图， 在直角梯形A B C D 中，A D ∥B C ，B C ＝5，C D ＝6，∠D C B ＝60°， ∠ABC ＝90°．等边三角形MPN （N 为不动点）的边长为a ，边MN 和直角梯形ABCD 的底边BC 都在直线l 上，NC ＝8．将直角梯形ABCD 向左翻折180°，翻折一次得到图形①，翻折二次得到图形②，如此翻折下去．（1） 求直角梯形ABCD 的面积；（2） 将直角梯形ABCD 向左翻折二次，如果此时等边三角形的边长a ≥2，请直接写出这时两图形重叠部分的面积是多少？（3） 将直角梯形ABCD 向左翻折三次，如果第三次翻折得到的直角梯形与等边三角形重叠部分的面积等于直角梯形ABCD 的面积，请直接写出这时等边三角形的边长a 至少应为多少？PNM DC BAl21yxQP OBA24．在矩形ABCD 中，点E 是AD 边上一点，连结BE ，且BE ＝2AE ， BD 是∠EBC 的平分线．点P 从点E 出发沿射线ED 运动，过点P 作PQ ∥BD 交直线BE 于点Q ．（1）当点P 在线段ED 上时（如图①），求证：33BE PD PQ =+； （2）当点P 在线段ED 的延长线上时（如图②），请你猜想33BE PD PQ 、、三者之间的数量关系（直接写出结果，不需说明理由）；（3）当点P 运动到线段ED 的中点时（如图③），连结QC ，过点P 作PF ⊥QC ，垂足为F ，PF 交BD 于点G ．若BC ＝12，求线段PG 的长．图图图321A BCDEQ PGPQ EDCBAP QEDC BA F25．如图，在平面直角坐标系xOy 中，已知点A （4，0），点B （0，3），点P 从点B 出发沿BA 方向向点A 匀速运动，速度为每秒1个单位长度，点Q 从点A 出发沿AO 方向向点O 匀速运动，速度为每秒2个单位长度，连结P Q ．若设运动的时间为t 秒 （0＜t ＜2）．（1）求直线AB 的解析式；（2）设△AQP 的面积为y ，求y 与t 之间的函数关系式； （3）是否存在某一时刻t ，使线段PQ 恰好把△AOB 的周长和面积同时平分？若存在，请求出此时t 的值；若不存在，请说明理由； （4）连结PO ，并把△PQO 沿QO 翻折，得到四边形PQP O '，那么是否存在某一时刻t ，使四边形PQP O '为菱形？若存在，请求出此时点Q 的坐标和菱形的边长；若不存在，请说明理由．数学练习（十一）参考答案12. 7 9 8.A20. 解：设抢修车的速度为x 千米/时，则吉普车的速度为1.5x 千米/时.由题意得1515151.560x x -=-----------------------2分 解得，x ＝20 -----------------------3分经检验x ＝20是原方程的根，并且符合题意. ------------------------4分 当x ＝20时，1.5x ＝30 ----------------------5分 答：抢修车的速度为20千米/时，吉普车的速度为30千米/时.21. 解：（1）直线1y x =+向左平移2个单位后得到直线l 的解析式为：y=x+3 - ----1分直线l 与y 轴的交点为：（0，3），与x 轴的交点为：（-3，0） ---------------3分 （2）∵直线l 与反比例函数ky x=的图象的交点为（2，-m ） ∴m=-5 -----------------------4分 ∴k=10∴反比例函数的解析式为：10y x=-----------------------5分 22.（1）垂直（CD ⊥OM ） - ------------------------------------2分（2）CM=290tan α-⋅ m ； ------------------------------------3分900<<α -------------------------------------4分25.解：（1）证明：延长EB 到G ，使BG=DF ，联结AG .∵∠ABG ＝∠ABC=∠D ＝90°, AB ＝AD ， ∴△ABG ≌△ADF .∴AG ＝AF, ∠1＝∠2． --------------------1分∴∠1+∠3＝∠2+∠3=∠EAF=12∠BAD ．∴∠GAE=∠EAF ． 又AE ＝AE ，∴△AEG ≌△AEF .∴EG ＝EF ． -----------------2分 ∵EG=BE+BG ．∴EF= BE ＋FD --------3分(2) (1)中的结论EF= BE ＋FD 仍然成立. ---------------------------4分（3）结论EF=BE ＋FD 不成立，应当是EF=B E －FD ．--------------------5分 证明：在BE 上截取BG ，使BG=DF ，连接AG ． ∵∠B+∠ADC ＝180°,∠ADF+∠ADC ＝180°，1图M P DC B A E Q∵AB ＝AD ，∴△ABG ≌△ADF .∴∠BAG ＝∠DAF,AG ＝AF ． ∴∠BAG+∠EAD ＝∠DAF+∠EAD=∠EAF =12∠BAD ．∴∠GAE=∠EAF ． ∵AE ＝AE ，∴△AEG ≌△AEF .∴EG ＝EF ---------------------6分 ∵EG=BE －BG∴EF=B E －FD ． ---------------------7分22．（本小题满分5分）EPN M DC BAl21解：（1）如图，过点D 作DE ⊥BC 于点E ． ∠ABC =90°， ∴AB DE ∥． 又AD BC ∥，∴四边形ABED 是矩形． ∴AD =BE ．在Rt △DEC 中，∠DCB =60°，∴DE = DC •sin 60°=6×32=33，……………………………………………1分 CE = DC ·cos60°=6×12=3．∴AD =BE =BC －CE =5－3=2．……………………………………………………2分 ∴直角梯形ABCD 的面积=1121()(25)333222AD BC DE +⋅=+⋅=．……………3分（2）重叠部分的面积等于3． ………………………………………………4分（3）等边三角形的边长a 至少为10． ………………………………………………5分24．（1）证明：如图①，∵四边形ABCD 是矩形， 90A ABC C ∴∠=∠=∠=︒，AD ∥BC ．EDB DBC ∴∠=∠． ∵BE ＝2AE ， 30ABE ∴∠=︒．E P DCBAQG NF图3∵BD 是∠EBC 的平分线，∴1302EBD DBC EBC EDB ∠=∠=∠=∠=︒．EB ED ∴=．PQ BD ∥，EQP EBD ∴∠=∠，EPQ EDB ∠=∠． 30EPQ EQP ∴∠=∠=︒，EQ EP ∴=．过点E 作EM QP ⊥垂足为M ，2PQ PM ∴=． 3cos cos302PM PE EPM PE PE =⋅∠=⋅︒=． 33PE PQ ∴=． ········································································ 1分 BE DE PD PE ==+，33BE PD PQ ∴=+． ································································· 2分 （2）解：当点P 在线段ED 的延长线上时，猜想：33BE PQ PD =-．…………………4分 （3）解：连结PC 交BD 于点N （如图③）点P 是线段ED 的中点，BE ＝DE ＝2AE ，BC ＝12， 4EP PD ∴==．tan 3043DC BC =⋅=，228PC PD DC ∴=+=，2283BD BC DC =+=．1cos 2PD DPC PC ∴∠==．60DPC ∴∠=．PQ BD ∥， 1432PQ BD ∴==． 18090QPC EPQ DPC ∠=-∠-∠=，90PND PNG ∠=∠=．122PN PD ∴==，2247QC PQ PC =+=． ·········································· 5分 90PGN FPC ∠=-∠，90PCF FPC ∠=-∠， PGN PCF ∴∠=∠．90PNG QPC ∠=∠=，PNG QPC ∴△∽△． ······································································· 6分 PG PN QC QP∴=．247221343PG ⨯∴==． ····································································· 7分 25．解：（1）设直线AB 的解析式为y kx b =+，∴40,3.k b b +=⎧⎨=⎩ 解得 3,43.k b ⎧=-⎪⎨⎪=⎩∴直线AB 的解析式是33y x +=-． ················································· 1分P 'NMA B OPQ xy （2）在Rt △AOB 中，225AB BO AO =+=，依题意，得BP = t ，AP = 5－t ，AQ = 2t ， 过点P 作PM ⊥AO 于M ． ∵△APM ∽△ABO ， ∴PM AP BO AB =．∴535PM t -=．∴335PM t =-．………………………2分∴211332(3)32255y AQ PM t t t t =⨯⨯=⨯⨯-=-+． ·································· 3分 （3）不存在某一时刻t ，使线段PQ 恰好把△AOB 的周长和面积同时平分．若PQ 把△AOB 周长平分，则AP+AQ=BP+BO+OQ ． ∴)24(32)5(t t t t -++=+-．解得1=t ． ················································································· 4分 若PQ 把△AOB 面积平分，则12APQ AOB S S ∆∆=． ∴－253t ＋3t =3．∵ t =1代入上面方程不成立，∴不存在某一时刻t ，使线段PQ 把△AOB 的周长和面积同时平分． ······· 5分（4）存在某一时刻t ，使四边形PQP O '为菱形．过点P 作 PN ⊥BO 于N ，若四边形PQP ′ O 是菱形，则有PQ ＝PO ．∵PM ⊥AO于M ，∴QM=OM ．∵PN ⊥BO于N ，可得△PBN ∽△ABO ．∴PN PB AO AB = ． ∴54t PN =．∴54t PN =．∴45t QM OM ==．∴425454=++t t t ．∴910=t ．∴当910=t 时，四边形PQP ′ O 是菱形． ········································ 6分 ∴OQ =4－2t =169．∴点Q 的坐标是（169，0）． ······························· 7分 ∵37533=-=t PM ，4859OM t ==， 在Rt △PMO 中，2249645059819PO PM OM =+=+=， ∴菱形PQP ′O 的边长为9505． ····················································· 8分。

七、一次函数（2）一、选择题题号 1 2 3 4 5 6 7 8 答案1.已知一次函数y=kx-k，若y随x的增大而减小，则该函数的图像经过（）A．第一、二、三象限 B．第一、二、四象限C．第二、三、四象限 D．第一、三、四象限2.已知一次函数y=kx+b（k、b是常数，且k≠0），x与y的部分对应值如下表所示，那么不等式kx+b＜0的解集是（）A.x＜0B.x＞0C.x＜1D.x＞13.如图，一次函数y=kx+b的图象经过A、B两点，则kx+b＞0的解集是（）A．x＞0 B．x＞2 C．x＞-3 D．-3＜x＜2第2题第3题4.一次函数y＝—2x＋3的图象与两坐标轴的交点是（）A．（0，3）（23，0） B．（1，3）（23，1） C．（3，0）（0，23） D．（3，1）（1，23）5.下面图像中，不可能是关于x的一次函数y= m x-(m-3)的图像的是 ( )A． B． C． D．6.一次函数y=kx+b中，-3≤x≤1时，对应的y值为1≤y≤9，则k、b的值为（）A．-2、3 B.2、-3或2、7 C.-2、7 D. 2、7或-2、37.若点P(a，b)关于x轴的对称点P′在第三象限，那么直线．y=ax+b的图像不经过（） A．第一象限 B．第二象限 C．第三象限 D．第四象限8.小明、小刚两同学从甲地出发骑自行车经同一条路线行驶到相距24千米的乙地，他们行驶的路程S (千米)和行驶时间t（小时）之间的函数关系如图所示，根据图中提供的信息，给出下列说法：①他们同时到达乙地；②小明在途中停留了1小时；③小刚出发后在距甲地8千米处与小明相遇；④他俩相遇后，小明的行驶速度小于小刚的行驶速度.其中正确的说法有 ( )A.1个B.2个C.3个D.4个x －2 －1 0 1 2 3y 3 2 1 0 －1 －2二、填空题9.一次函数的图象过点（-1，0），且函数值随着自变量的增大而减小，写出一个符合这个条件的一次函数的解析式：__ _______．10.如图，已知函数y=ax+b和y=kx的图象交于点P，则根据图象可得，关于y ax by kx=+⎧⎨=⎩的二元一次方程组的解是______ __．11.点M（-2，k）在直线y=2x+1上，M到y轴的距离=_________.12.若直线y=2x+6与直线y=mx+5平行，则m=____________.13.已知一次函数y=kx+b的图象经过点P（2，－1）与点Q（－1，5），则当y的值增加1时，x的值将_______________________.14.直线y=2x＋3可以看成是将直线y=2x沿y轴向上平移3个单位而得到的，那么将y=2x 沿x轴向右平移3个单位得到的直线方程是．15.某厂现在的年产值是15万元，计划今后每年增加2万元，年产值y与年数x之间的函数关系为，五年后产值是．16.日常生活中，“老人”是一个模糊概念，•有人想用“老人系数”来表示一个人的老年化程度，其中一个人的“老人系数”计算方法如下表：人的年龄x（岁）x≤60 60<x<80 x≥80该人的“老人系数”06020x-1．三、解答题16.已知y+b与x+ n成正比例(其中b、n是常数).(1)试说明y是x的一次函数；(2)若x=3时，y=5，x=2时y=2，试写出这个函数关系式.17.用图象法解二元一次方程组:32, 23 5. x yx y-=⎧⎨+=⎩18.一个弹簧，不挂物体时长12cm ，挂上物体后会伸长，伸长的长度与所挂物体的质量成正比例．如果挂上3kg 物体后，弹簧总长是13.5cm ，求弹簧总长y(cm)与所挂物体质量x(kg)之间的函数关系式．19.夏天容易发生腹泻等肠道疾病， 某医药公司的甲、乙两仓库内分别存有医治腹泻的药品80箱和70箱，现需要将库存的药品调往南县100箱和沅江50箱，已知从甲、乙两仓库运送药品到两地的费用(元／箱)如下表所示：(1)设从甲仓库运送到南县的药品为x 箱，求总费用y(元)与x(箱)之间的函数关系式，并写出x 的取值范围； (2)求出最低费用，并说明总费用最低时的调配方案．20.小明受《乌鸦喝水》故事的启发，•利用量筒和体积相同的小球进行了如下操作： 请根据图中给出的信息，解答下列问题：（1）放入一个小球量筒中水面升高__ _____cm ；（2）求放入小球后量筒中水面的高度y （cm ）与小球个数x （个）•之间的一次函数关系式（不要求写出自变量的取值范围）；（3）量筒中至少放入几个小球时有水溢出？县名 费用(元／箱) 甲仓库 乙仓库 南县 14 20 沅江 10 8。