湖南省永州市高三一轮模拟考试试卷及答案
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2024-2025学年湖南省永州市高三(第一次)模拟考试物理试卷一、单选题:本大题共6小题,共24分。
1.我国正在建设的大科学装置——“强流重离子加速器”。
其科学目标之一是探寻神秘的“119号”元Am→A119X+210n产生该元素。
关于原子核Y和质量数A,下列选项正确素,科学家尝试使用核反应Y+24395的是( )A. Y为 5826Fe,A=299B. Y为 5826Fe,A=301C. Y为 5424Cr,A=295D. Y为 5424Cr,A=2972.2024年8月3日,中国选手郑钦文在巴黎奥运会网球女单决赛中战胜克罗地亚选手维基奇夺冠,为中国网球赢得史上首枚女单奥运金牌。
如图所示,网球比赛中,运动员甲某次在B点直线救球倒地后,运动员乙将球从距水平地面上D点高度为ℎ的A点水平击出,落点为C。
乙击球瞬间,甲同时沿直线BC奔跑,恰好在球落地时赶到C点。
已知BC⊥BD,BD=d,BC=l,网球和运动员甲均可视为质点,忽略空气阻力,则甲此次奔跑的平均加速度大小与当地重力加速度大小之比为( )A. lℎB. 2dlC. d2+l2ℎD. d d2+l2ℎl3.如图所示,一装满某液体的长方体玻璃容器,高度为a,上下两个面为边长32a的正方形,底面中心O 点放有一单色点光源,可向各个方向发射单色光。
液面上漂浮一只可视为质点的小甲虫,已知该液体对该单色光的折射率为n=2,则小甲虫能在液面上看到点光源的活动区域面积为( )A. 18a2πa3B. 13C. πa2D. a24.假设某空间有一静电场的电势φ随x变化情况如图所示,且带电粒子的运动只考虑受电场力,根据图中信息可以确定下列说法中正确的是( )A. 从x2到x3,场强的大小均匀增加B. 正电荷沿x轴从O运动到x1的过程中,做匀加速直线运动C. 负电荷沿x 轴从x 4移到x 5的过程中,电场力做正功,电势能减小D. x 2处场强大小为E 2,x 4处场强大小为E 4,则E 2>E 45.中国载人登月初步方案已公布,计划2030年前实现载人登月科学探索。
2024届湖南省永州市高三上学期第一次模拟考试全真演练物理试题一、单项选择题(本题包含8小题,每小题4分,共32分。
在每小题给出的四个选项中,只有一项是符合题目要求的)(共8题)第(1)题太阳内部热核反应的主要模式是质子-质子循环,循环的结果可以表示为,则核反应方程中粒子X为( )A.电子B.正电子C.中子D.质子第(2)题阴历正月十五放花灯,称为灯节,或称“元宵节”。
这一天,人们有观灯和吃元宵的习惯。
人们将制作好的花灯,点上蜡烛,放入河中漂流,供大家欣赏。
若河水各点流速与该点到较近河岸边的距离成正比,现将花灯以一定速度垂直河岸推出去,假设花灯垂直河岸的速度不变,则花灯到达对岸的运动路径正确的是( )A.B.C.D.第(3)题如图,矩形abcd为匀强磁场区域,磁场方向竖直向下,圆形闭合金属线圈以一定的速度沿光滑绝缘水平面向磁场区域运动。
下图是线圈的四个可能到达的位置,则线圈的速度不可能为零的位置是( )A.B.C.D.第(4)题两足够长的细直导线和相互绝缘,彼此贴近,按图示方式放置,二者可近似视为在同一平面内,两长直导线中通有大小相等的电流I,电流方向如图所示,若一根无限长直导线通过电流I时,所产生的磁场在距离导线d处的磁感应强度大小为B,则图中与导线距离均为d的M、N两点处的磁感应强度大小分别为()A.0、0B.B、0C.B、B D.、第(5)题电容器是一种重要的电学元件,在电工、电子技术中应用广泛。
使用图甲所示电路观察电容器的充、放电过程。
电路中的电流传感器与计算机相连,可以显示电路中电流随时间的变化。
图甲中直流电源电动势,实验前电容器不带电。
先使S与“1”端相连给电容器充电,充电结束后,使S与“2”端相连,直至放电完毕。
计算机记录的电流随时间变化的曲线如图乙所示。
下列说法正确的是( )A.图像阴影为图像与对应时间轴所围成的面积表示电容器的能量B.阴影部分的面积和肯定不相等C.阻值大于D.计算机测得,则该电容器的电容约为0.15F第(6)题如图所示,长的细绳的一端固定与点,另一端系一质量为的小球,使小球在竖直平面内做圆周运动,当小球在最高点时绳的拉力为,则小球在最高的的速度为( )A.B.C.D.第(7)题2024年1月天津大学科研团队攻克了长期以来阻碍石墨烯电子学发展的关键技术难题,打开了石墨烯带隙,开启了石墨烯芯片制造领域“大门”。
永州市2024年高考第一次模拟考试数学(答案在最后)注意事项:1.全卷满分150分,时量120分钟.2.全部答案在答题卡上完成,答在本试题卷上无效.3.考试结束后,只交答题卡.一、选择题:本题共8小题,每小题5分,共40分在每小题给出的四个选项中,只有一项是符合题目要求的.1.已知集合{*N A x y =∈=,集合{}20B x x x =-≥,则A B = ()A.{}12x x ≤≤ B.{}01x x ≤≤ C.{}0,1,2 D.{}1,2【答案】D 【解析】【分析】求出集合,A B ,即可求得答案.【详解】由{{}*N 1,2A x y =∈==,{}20{|0B x x x x x =-≥=≤或1}x ≥,故{}1,2A B = ,故选:D2.复数z 满足5i 1i z ⋅=+,则z 在复平面内对应的点位于()A.第一象限B.第二象限C.第三象限D.第四象限【答案】D 【解析】【分析】根据虚数单位的性质,结合复数的除法运算可求出z ,根据复数的几何意义即可得答案.【详解】由5i 1i z ⋅=+得1ii 1i,iz z +⋅=+∴=,则111i iz =+=-,即z 在复平面内对应的点为(1,1)-,位于第四象限,故选:D3.已知向量()()()1,2,3,1,,1a b c x =-=-=,且()2a b c +⊥ ,则x =()A.2 B.1 C.0D.1-【答案】C【解析】【分析】根据向量垂直列方程,由此求得x 的值.【详解】()()()21,26,25,0a b +=-+-=,由于()2a b c +⊥,所以()250,0a b c x x +⋅=== .故选:C4.“函数()af x x =在()0,∞+上单调递减”是“函数()()41g x x a x =-+是偶函数”的()A.充分不必要条件B.必要不充分条件C.充要条件D.既不充分也不必要条件【答案】B 【解析】【分析】通过求解函数()f x 和()g x 符合条件的a 的取值,即可得出结论.【详解】由题意,在()af x x =中,当函数在()0,∞+上单调递减时,a<0,在()()41g x x a x =-+中,函数是偶函数,∴()()()()()()()()4411g x x a x g x x a x g x g x ⎧-=--+-⎪=-+⎨⎪=-⎩,解得:1a =-,∴“函数()af x x =在()0,∞+上单调递减”是“函数()()41g x x a x =-+是偶函数”的必要不充分条件,故选:B.5.在平面直角坐标系中,过直线230x y --=上一点P 作圆22:21C x x y ++=的两条切线,切点分别为A B 、,则sin APB ∠的最大值为()A.265B.5C.65D.5【答案】A 【解析】【分析】由题意圆22:21C x x y ++=的标准方程为()2:12C x y ++=,如图sin sin 22sin cos APB ααα∠==,又sin AC CPα==,所以cos α==又由圆心到直线的距离可求出CP 的最小值,进而求解.【详解】如下图所示:由题意圆C 的标准方程为()2:12C x y ++=,sin sin 22sin cos APB ααα∠==,又因为sin AC CPα==cos α==所以sin 2sin cos PB A αα∠==又圆心()1,0C -到直线230x y --=的距离为d ==,所以CP d ≥=,所以不妨设211,05t t CP⎛⎫=<≤ ⎪⎝⎭,则()s n i f t APB ===∠=,又因为()f t 在10,5⎛⎤⎥⎝⎦单调递增,所以当且仅当15t =即CP =CP 垂直已知直线230x y --=时,sin APB ∠有最大值()max155sin f APB ⎛⎫== ⎪∠⎝⎭.故选:A.6.已知椭圆2222:1(0)x y C a b a b+=>>的左、右焦点分别是12,F F ,点P 是椭圆C 上位于第一象限的一点,且2PF 与y 轴平行,直线1PF 与C 的另一个交点为Q ,若1125PF F Q =,则C 的离心率为()A.7B.11C.7D.2111【答案】B 【解析】【分析】由P 点坐标求得Q 点坐标,然后代入椭圆C 的方程,化简求得椭圆C 的离心率.【详解】由22221x y a b +=令x c =,得24222221,c b b y b y a a a ⎛⎫=-==± ⎪⎝⎭,由于2PF 与y 轴平行,且P 在第一象限,所以2,b P c a ⎛⎫⎪⎝⎭.由于()111112,,5502,PF F Q F Q PF F c ==-,所以()2211292,02,,555b b OQ OF FQ c c c a a ⎛⎫⎛⎫=+=-+--=-- ⎪ ⎪⎝⎭⎝⎭,即292,55b Q c a ⎛⎫-- ⎪⎝⎭,将Q 点坐标代入椭圆C 的方程得2222229551b c a a b ⎛⎫⎛⎫-- ⎪ ⎪⎝⎭⎝⎭+=,()22222222222814814774125252525c a c c b c a a a a a +-++===,222222221377425,7721,7711c c a a c a a +====,所以离心率11c e a ===.故选:B7.若数列{}n a 的前n 项和为()2*,21N ,0n n n n n S S a a n a =+∈>,则下列结论正确的是()A.202220231a a >B.2023a >C.2023S <D.123100111119S S S S ++++< 【答案】D 【解析】【分析】根据,n n a S之间的关系可求出=n S,进而求得=n a ,由此结合熟的大小比较可判断A ,B ,C ,利用放缩法,当2n ≥时,可推出1nS <,累加即可判断D.【详解】令1n =,则121121S a a =+,即221121a a =+,由0n a >,的11a =;当2n ≥时,2112()()1n n n n n S S S S S ---=-+,即1221n n S S --=,又22111S a ==,故{}n S 为首项是1,公差为1的等差数列,则211n S n n =+-=,故=n S ,所以当2n ≥时,1-=-=n n n a S S 11a =也适合该式,故=n a ,对于A,20222023a a =1=,A 错误;对于B,2023a <=,B 错误;对于C,2023S >=C 错误;对于D ,当2n ≥时,1n S =<=,故)123100111112122S S S S ++++<+-+++ 12(110)19=+-+=,D 正确,故选:D8.已知函数()()3cos (0)f x x ωϕω=+>,若ππ3,042f f ⎛⎫⎛⎫-== ⎪ ⎪⎝⎭⎝⎭,在区间ππ,36⎛⎫-- ⎪⎝⎭上没有零点,则ω的取值共有()A.4个 B.5个C.6个D.7个【答案】B 【解析】【分析】根据ππ3,042f f ⎛⎫⎛⎫-== ⎪ ⎪⎝⎭⎝⎭可得234+3n ω=,根据在区间ππ,36⎛⎫-- ⎪⎝⎭上没有零点可得06ω<≤,即可求出ω的取值有几个.【详解】由题意,在()()3cos (0)f x x ωϕω=+>中,ππ3,042f f ⎛⎫⎛⎫-== ⎪ ⎪⎝⎭⎝⎭,∴π3cos 34π3cos 02ωϕωϕ⎧⎛⎫-+= ⎪⎪⎪⎝⎭⎨⎛⎫⎪+= ⎪⎪⎝⎭⎩,所以1122π2π4,,Z πππ+22k k k k ωϕωϕ⎧-+=⎪⎪∈⎨⎪+=⎪⎩,两式相减得()213ππ2π+42k k ω-=,所以()212432+3k k ω-=,即234+3n ω=,Z n ∈,因为ππ,,306x ω⎛⎫∈-- ⎪⎝>⎭,所以ππ,36x ωϕωϕωϕ⎛⎫∈--++ ⎝+⎪⎭,令x t ωϕ+=,ππ,36t ωϕωϕ++⎛⎫∈-- ⎪⎝⎭,由题意知3cos y t =在ππ,36t ωϕωϕ++⎛⎫∈-- ⎪⎝⎭上无零点,故ππππ,,3622ππk k ωϕωϕ⎛⎫⎛⎫--⊆- ⎪ ⎪⎝++⎝++⎭⎭,Z k ∈,所以πππ32πππ62k k ωϕωϕ⎧-+≥-+⎪⎪⎨⎪-+≤+⎪⎩,即πππ32πππ62k k ωϕωϕ⎧-+≥-+⎪⎪⎨⎪-≥--⎪⎩,两式相加得ππ6ω-≥-,所以06ω<≤,又234+3n ω=,所以,当0n =时,23ω=;当1n =时,2ω=;当2n =时,103ω=;当3n =时,143ω=;当4n =时,6ω=,所以ω的取值有5个.故选:B.二、多项选择题:本题共4小题,每小题5分,共20分.在每小题给出的选项中,有多项符合题目要求.全部选对的得5分,有选错的得0分,部分选对的得2分.9.下列关于概率统计说法中正确的是()A.两个变量,x y 的相关系数为r ,则r 越小,x 与y 之间的相关性越弱B.设随机变量()2,1N ξ ,若(3)p p ξ>=,则1(12)2p p ξ<<=-C.在回归分析中,2R 为0.89的模型比2R 为0.98的模型拟合得更好D.某人解答10个问题,答对题数为(),10,0.8X X B ~,则()8E X =【答案】BD 【解析】【分析】A 项,通过相关系数的定义即可得出结论;B 项,通过求出(23)P ξ<<即可求出(10)P ξ-<<的值;C 项,通过比较相关指数即可得出哪个模型拟合更好;D 项,通过计算即可求出()E x .【详解】由题意,A 项,两个变量,x y 的相关系数为r ,r 越小,x 与y 之间的相关性越弱,故A 错误,对于B,随机变量ξ服从正态分布(2,1)N ,由正态分布概念知若(3)P p ξ>=,则1(10)(23)(2)(3)2P P P P p ξξξξ-<<=<<=>->=-,故B 正确,对于C ,在回归分析中,2R 越接近于1,模型的拟合效果越好,∴2R 为0.98的模型比2R 为0.89的模型拟合的更好故C 错误,对于D ,某人在10次答题中,答对题数为,~(10,0.8)X X B ,则数学期望()100.88E X =⨯=,故D 正确.故选:BD.10.对数的发明是数学史上的重大事件.我们知道,任何一个正实数N 可以表示成10(110,)n N a a n =⨯≤<∈Z 的形式,两边取常用对数,则有lg lg N n a =+,现给出部分常用对数值(如下表),下列结论正确的是()真数x2345678910lg x (近似值)0.3010.4770.6020.6990.7780.8450.9030.954 1.000真数x111213141516171819lg x (近似值) 1.041 1.079 1.1141.1461.1761.2041.2301.2551.279A.105在区间()6710,10内B.503是15位数C.若50710m a -=⨯,则43m =-D.若()30*mm N ∈是一个35位正整数,则14m =【答案】ACD 【解析】【分析】根据lg lg N n a =+,分别求出各个选项中N 的常用对数的值,对照所给常用对数值判断.【详解】解:因为10lg 510lg 5 6.99=≈,67lg106lg106 6.99,lg107lg107 6.99==<==>,所以()1067510,10∈,故A 正确;因为505023.85lg 350lg 323.85,310=≈≈,所以503是24位数,故B 错误;因为50lg 750lg 742.25-=-≈-,所以5042.25710--≈,又50710m a -=⨯,则43m =-,故C 正确;30lg 30lg m m =,因为()30*mm N ∈是一个35位正整数,所以3430lg 35m ≤<,即177lg 156m ≤<,即1.1267lg 1.1667m ≤<,则14m =,故D 正确.故选:ACD11.菱形ABCD 的边长为a ,且60BAD ∠= ,将ABD △沿BD 向上翻折得到PBD △,使二面角P BD C --的余弦值为13,连接PC ,球O 与三棱锥P BCD -的6条棱都相切,下列结论正确的是()A.PO ⊥平面BCDB.球O 的表面积为22πaC.球O 被三棱锥P BCD -表面截得的截面周长为π3a D.过点O 与直线,PB CD 所成角均为π4的直线可作4条【答案】AC 【解析】【分析】利用余弦定理求得PC a =,说明三棱锥P BCD -为正四面体,进而补成正方体,则说明O 点为正方体的中心,结合线面垂直的判定可判断A ;求得球O 的半径可判断B ;求出球O 被三棱锥一个侧面所截得的截面的周长,即可求得球O 被三棱锥P BCD -表面截得的截面周长,判断C ;根据平行公理以及直线所成角的概念可判断D.【详解】如图在菱形ABCD 中,连接AC ,则AC BD ⊥,设,AC BD 交于E ,则,PE BD CE BD ⊥⊥,PE ⊂平面PBD ,CE ⊂平面CBD ,即PEC ∠为二面角P BD C --的平面角,即1cos 3PEC ∠=,又60BAD ∠= ,即ABD △为正三角形,即PBD △,CBD △为正三角形,故2PE CE a ==,故2222cos PC PE CE PE CE PEC =+-⋅∠2223312243a a a =-⨯⨯=,即PC a =,故三棱锥P BCD -为棱长为a 的正四面体;如图,将该四面体补成正方体PHDG NCMB -,四面体的各棱为正方体的面对角线,则正方体棱长为2a ,因为球O 与三棱锥P BCD -的6条棱都相切,则O 点即为正方体的中心,连接PM ,则O 为正方体体对角线PM 的中点,因为PN ^平面,MBNC BC ⊂平面MBNC ,故PN BC ⊥,又BC MN ⊥,而,,PN MN N PN MN =⊂ 平面PMN ,故BC ⊥平面PMN ,PM ⊂平面PMN ,故BC PM ⊥;同理可证BD PM ⊥,,,⋂=⊂BC BD B BC BD 平面BCD ,故PM ⊥平面BCD ,即PO ⊥平面BCD ,A 正确;因为球O 与三棱锥P BCD -的6条棱都相切,故球O 即为正方体PHDG NCMB -的内切球,球的直径为正方体棱长2a ,则球的半径为24a ,故球O 的表面积为2214)ππ42a a ⨯=,B 错误;球O 被平面截得的截面圆即为正三角形BCD 的内切圆,由于BC a =,故正三角形BCD 的内切圆半径为1326a a ⨯=,故内切圆周长即球O 被平面截得的截面圆周长为2ππ63a a ⨯=,故球O 被三棱锥P BCD -表面截得的截面周长为3434ππ33a a ⨯=,C 正确;连接HM ,因为,PH BM PH BM =∥,即四边形PHMB 为平行四边形,故PB HM ∥,而HM CD ⊥,故PB CD ⊥,不妨取空间一点S ,作,PB CD 的平行线,P B C D '''',如图,则和,P B C D ''''所成角均为π4的直线即为它们形成的角的角平分线12,l l ,假设平面α过1l 且垂直于,P B C D ''''所确定的平面,当1l 绕点S 且在α内转动时,则此时直线l 与,P B C D ''''所成角相等,但会变大,大于π4,即在,P B C D ''''所确定的平面外过点S 不存在直线l 与,P B C D ''''所成角为π4,故过点O 与直线,PB CD 所成角均为π4的直线可作2条,D 错误,故选:AC12.已知函数()f x 与()g x 的定义域均为R ,()()()()123,11f x g x f x g x ++-=---=,且()12g -=,()1g x -为偶函数,下列结论正确的是()A.4为()f x 的一个周期B.()31g =C.20231()4045k f k ==∑ D.20231()2023k g k ==∑【答案】ACD 【解析】【分析】根据函数的奇偶性、周期性进行分析,从而确定正确答案.【详解】由于()1g x -为偶函数,图象关于y 轴对称,所以()g x 图象关于=1x -对称,所以()()()()()()21111g x g x g x g x -=-+-=---=-,所以()()()()1213f x g x f x g x ++-=++-=①,而()()11f x g x ---=②,两式相加得()()114f x f x -++=,则()()24f x f x ++=③,所以()()()()()()4224244f x f x f x f x f x +=++=-+=--=,所以4是()f x 的一个周期,A 选项正确.由③令1x =得()()134f f +=,由①令2x =得()()()()21223,21f g f f +-=+==,由②令1x =得()()()()01021,03f g f f --=-==,则()()403f f ==,所以()()()()()()()12348,1235f f f f f f f +++=++=,所以()()()202312020()81234040540454k f k f f f ==⨯+++=+=∑,C 选项正确.由①令=1x -得()()()()01313,10f g g g +=+==,由()()()()123,11f x g x f x g x ++-=---=,得()()()()33,11f x g x f x g x +-=---=,两式相减得()()312g x g x -+--=,即()()312g x g x -+-=,且()g x 关于()2,1-对称,()21g -=,所以()()22g x g x ++=④,所以()()()()()()4222222g x g x g x g x g x +=++=-+=--=,所以()g x 是周期为4的周期函数,所以()()312g g =-=,所以B 选项错误.由④令2x =得()()242g g +=,所以()()()()12344g g g g +++=,由于()()()22421g g g =-+=-=,所以()()()1233g g g ++=所以202312020()4320234k g k ==⨯+=∑,所以D 选项正确.故选:ACD【点睛】有关函数的奇偶性、周期性的题目,关键是要掌握抽象函数运算,还要记忆一些常用的结论.如()()()()()(),,kf x A f x f x a f x f x a f a +=+=-+=等等,这些都是与周期性有关;如()()()(),f a x f a x f a x f a x +=-+=--等等,这些都是与对称性有关.三、填空题:本题共4小题,每小题5分,共20分.13.为全面推进乡村振兴,永州市举办了“村晚兴乡村”活动,晚会有《走,去永州》《扬鞭催马运粮忙》《数幸福》《乡村振兴唱起来》四个节目,若要对这四个节目进行排序,要求《数幸福》与《乡村振兴唱起来》相邻,则不同的排列种数为________(用数字作答).【答案】12【解析】【分析】利用捆绑求得正确答案.【详解】由于《数幸福》与《乡村振兴唱起来》相邻,所以两者“捆绑”,则不同的排列种数为2323A A 12=种.故答案为:1214.在平行六面体1111ABCD A B C D -中,1,,,DA a DC b DD c P ===为1DD 的中点,过PB 的平面α分别与棱11,AA CC 交于点,E F ,且AE CF =,则BP EF +=________(用,,a b c表示).【答案】122a c-+【解析】【分析】由题意设Q R E F 、、、分别为11,,,QA RC AA CC 的中点,容易证明四边形PEBF 是平行四边形,即平面PEBF 为符合题意的平面α,进而分解向量即可求解.【详解】如图所示:由题意不妨设Q R E F 、、、分别为11,,,QA RC AA CC 的中点,容易证明四边形PEBF 是平行四边形,即平面PEBF 为符合题意的平面α,因此()()()()BP EF BD ED DF D F DP DC D A P DE D ++=+=+++---+ ,又因为112DP DD = ,DE DA AE -=-- ,DF DC CF =+,且114AE DD = ,114CF DD = ,所以1111111112222442B D D DC DD A DD DC DA D F c P E D a A --+--+++⎛⎫⎛⎫+=+=-- ⎪ ⎪⎝+⎭⎝⎭=.故答案为:122a c -+.15.若函数()()e 2ln 2txtxf x x x +=-+,当()0,x ∈+∞时,()0f x >,则实数t 的取值范围________.【答案】1,e⎛⎫+∞ ⎪⎝⎭【解析】【分析】由()0f x >进行转化,利用构造函数法,结合多次求导来求得t 的取值范围.【详解】依题意,当()0,x ∈+∞时,()()e 2ln 02txtxf x x x +=->+恒成立,即()()e 22ln txtx x x +>+恒成立,即()()e 2ln e 2ln txtxx x +⋅>+①恒成立,设()()2ln g x x x =+,()21ln g x x x'=++,令()()()2221ln ,x h x g x x h x x x -''==++=,所以()h x 在区间()0,2上()()0,h x h x '<单调递减;在区间()2,+∞上()()0,h x h x '>单调递增,所以()()22ln 20h x h ≥=+>,也即()0g x '>,()g x 在()0,∞+上单调递增,所以由①得e tx x >,即ln ln ,xtx x t x>>,设()()2ln 1ln ,x x m x m x x x-'==,所以()m x 在区间()0,e 上()()0,m x m x '>单调递增;在区间()e,+∞上()()0,m x m x '<单调递减,所以()()ln e 1e e em x m ≤==,所以1e t >,即t 的取值范围是1,e ⎛⎫+∞ ⎪⎝⎭.故答案为:1,e ⎛⎫+∞ ⎪⎝⎭16.已知点((0)N a a >在抛物线2:2(02)C y px p a =<<上,F 为抛物线C 的焦点,圆N 与直线2px =相交于A B 、两点,与线段NF 相交于点R ,且AB =.若R 是线段NF 上靠近F 的四等分点,则抛物线C 的方程为________.【答案】24y x =【解析】【分析】设||4(0)NF t t =>,表示出|,|AB RF t ===,利用抛物线定义、点在抛物线上以及圆的弦长的几何性质列出关于,a p 的方程,即可求得p ,即得答案.【详解】由2:2(02)C y px p a =<<可知(,0)2pF ,设||4(0)NF t t =>,则|,|AB RF t ===,则||3NR t =,故222||(()||22p AB a NR -+=,即222()92p a t -+=①;又点((0)N a a >在抛物线2:2(02)C y px p a =<<上,故||42pNF a t =+=②,且122pa =,即6pa =③,②联立得22122030a ap p -+=,得23a p =或6a p =,由于02p a <<,故23a p =,结合6pa =③,解得2p =,故抛物线方程为24y x =,故答案为:24y x=【点睛】关键点睛:解答本题的关键在于要结合抛物线的定义以及圆的弦长的几何性质,找出参数,a p 间的等量关系,从而列出方程组,即可求解.四、解答题:本题共6小题,共70分.解答应写出文字说明、证明过程或演算步骤.17.已知数列{}n a 是公比1q >的等比数列,前三项和为39,且123,6,a a a +成等差数列.(1)求数列{}n a 的通项公式;(2)设()*3213211N log log n n n b n a a -+=∈⋅,求{}n b 的前n 项和n T .【答案】(1)3nn a =(2)21n nT n =+【解析】【分析】(1)根据题意列出方程组,求出首项和公比,即可得答案;(2)利用(1)的结论化简()*3213211N log log n n n b n a a -+=∈⋅,利用裂项求和法即可求得答案.【小问1详解】由题意可得123213392(6)a a a a a a ++=⎧⎨+=+⎩,即得22239,92(6)a a a +=∴=+,则1330a a +=,即1219(1)30a q a q =⎧⎨+=⎩,可得231030q q -+=,由于1q >,故得3q =,则13a =,故1333n nn a -=⨯=;【小问2详解】由(1)结论可得2132133231213)111log log log log 3(21)(21n n n n n b a a n n +--+===⋅⋅-+111()22121n n =--+,故{}n b 的前n 项和111111(1)23352121n T n n =-+-++--+ 11(122121n n n =-=++.18.在ABC 中,设,,A B C 所对的边分别为,,a b c ,且满足cos cos c A a C a b -=+.(1)求角C ;(2)若5,c ABC =的内切圆半径4r =,求ABC 的面积.【答案】(1)2π3(2)16【解析】【分析】(1)利用正弦定理边化角,结合两角和的正弦公式化简,可得cos C 的值,即可得答案;(2)利用余弦定理得2225a b ab +=-,配方得2()25a b ab +=+,再结合ABC 的内切圆半径,利用等面积法推出25a b ab +=-,即可求得214ab =,从而求得答案.【小问1详解】在ABC 中,由cos cos c A a C a b -=+得sin cos sin cos sin sin C A A C A B -=+,即sin cos sin cos sin sin()C A A C A A C -=++,故2sin cos sin A C A -=,由于(0,π),sin 0A A ∈∴≠,故1cos 2C =-,而(0,π)C ∈,故2π3C =.【小问2详解】由2π3C =可得222c a b ab =++,而5c =,故2225a b ab +=-,则2()25a b ab +=+,由ABC 的内切圆半径34r =,可得11()sin 22a b c r ab C ++⋅=,即5()42a b ++=,即25a b ab +=-,故2(25)25ab ab -=+,解得214ab =,故ABC 的面积1121sin 224216S ab C ==⨯⨯=.19.如图所示,在四棱锥P ABCD -中,底面ABCD 为矩形,侧面PAD 为正三角形,且24,AD AB M N ==、分别为PD BC 、的中点,H 在线段PC 上,且3PC PH =.(1)求证://MN 平面PAB ;(2)当AM PC ⊥时,求平面AMN 与平面HMN 的夹角的余弦值.【答案】(1)证明见解析(2)15【解析】【分析】(1)取AD 中点Q ,连接,MQ NQ ,要证//MN 平面PAB ,只需平面//MQN 平面PAB ,结合已知条件即可得证.(2)当AM PC ⊥时并结合已知条件即可建立如图所示坐标系,根据24==A D A B 以及中点关系、3PC PH =即可写出各个点的坐标,进而求出法向量即可求解.【小问1详解】如图所示:取AD 中点Q ,连接,MQ NQ ,,M N 分别为PD BC 、的中点,且底面ABCD 为矩形,所以1//,2MQ PA MQ PA =,且//NQ AB ,又因为MQ Ì平面MQN ,MQ ⊄平面PAB ,NQ ⊂平面MQN ,NQ ⊄平面PAB ,所以//MQ 平面PAB ,且//QN 平面PAB ,又因为MQ NQ Q = ,MQ Ì平面MQN ,NQ ⊂平面MQN ,所以平面//MQN 平面PAB ,因为MN ⊂平面MQN ,所以由面面平行的性质可知//MN 平面PAB 【小问2详解】如图所示:注意到侧面PAD 为正三角形以及M 为PD 的中点,所以由等边三角形三线合一得AM PD ⊥,又因为AM PC ⊥,且PD ⊂面PDC ,PC ⊂面PDC ,PD PC P ⋂=,所以AM ⊥面PDC ,又因为CD ⊂面PDC ,所以CD AM ⊥,又因为底面ABCD 为矩形,所以CD AD ⊥,因为AD AM A = ,AM ⊂面PAD ,AD ⊂面PAD ,所以CD ⊥面PAD ,因为PQ ⊂面PAD ,所以CD PQ ⊥,又//CD NQ ,所以NQ PQ ⊥,又由三线合一PQ AD ⊥,又AD NQ ⊥,所以建立上图所示的空间直角坐标系;因为24==A D A B ,所以()()(()()0,2,0,2,0,0,0,0,3,2,2,0,0,2,0A N P C D -,又因为M 为PD 的中点,3PC PH =,所以(22433,,,333M H ⎛⎫⎪ ⎪⎝⎭,所以(0,3,3MA =- ,(2,1,3MN =- ,213,,333MH ⎛⎫=- ⎪ ⎪⎝⎭ ,不妨设平面AMN 与平面HMN 的法向量分别为()()11112222,,,,,n x y z n x y z ==,所以有1100n MA n MN ⎧⋅=⎪⎨⋅=⎪⎩ 以及2200n MH n MN ⎧⋅=⎪⎨⋅=⎪⎩,即分别有11111330230y x y z ⎧-=⎪⎨-=⎪⎩以及2222222130333230x y z x y z ⎧-+=⎪⎨⎪-=⎩,分别令121,1y x =-=,并解得(()121,1,3,1,2,0n n =-=,不妨设平面AMN 与平面HMN 的夹角为θ,所以12121cos 5n n n n θ⋅==⋅ ;综上所述:平面AMN 与平面HMN 的夹角的余弦值为15.20.某企业为提高竞争力,成功研发了三种新品、、A B C ,其中、、A B C 能通过行业标准检测的概率分别为469,,5710,且、、A B C 是否通过行业标准检测相互独立.(1)设新品、、A B C 通过行业标准检测的品种数为X ,求X 的分布列;(2)已知新品A 中的一件产品经检测认定为优质产品的概率为0.025,现从足量的新品A 中任意抽取一件进行检测,若取到的不是优质产品,则继续抽取下一件,直至取到优质产品为止,但抽取的总次数不超过n .如果抽取次数的期望值不超过5,求n 的最大值.参考数据:456780.9750.904,0.9750.881,0.9750.859,0.9750.838,0.9750.817≈≈===【答案】(1)分布列见解析(2)5【解析】【分析】(1)由题意X 的所有可能取值为:0,1,2,3,由独立事件乘法公式以及互斥事件加法公式即可分别求出相应的概率,进而求解.(2)不妨设抽取第()11k k n ≤≤-次时取到优质产品,此时对应的概率为()()10.0250.975k P k -=⨯,而第n 次抽到优质产品的概率为()()10.975n P n -=,所以抽取次数的期望值为()()()()()1111110.0250.9750.975n n k n k k E n k P k nP n k n ----==⎡⎤⎡⎤=⋅+=⨯⋅+⎢⎥⎢⎥⎣⎦⎣⎦∑∑()()()210.025120.97510.9750.975n n n n --⎡⎤=⨯+⨯++-⨯+⎣⎦,对其求和并结合()5E n ≤以及参考数据即可求解.【小问1详解】由题意X 的所有可能取值为:0,1,2,3.()111157103500P X =⨯⨯==,()411161119195710571057100135P X =⨯⨯+⨯⨯+⨯=⨯=,()461419169114575710571057103501752P X =⨯⨯+⨯⨯+===⨯⨯,()46921610857103505317P X =⨯⨯===;所以X 的分布列如下表:X 0123()P X 13501935057175108175【小问2详解】不妨设抽取第()11,2k k n n ≤≤-≥次时取到优质产品,此时对应的概率为()()10.0250.975k P k -=⨯,而第n 次抽到优质产品的概率为()()10.975n P n -=,因此由题意抽取次数的期望值为()()()()()1111110.0250.9750.975n n k n k k E n k P k nP n k n ----==⎡⎤⎡⎤=⋅+=⨯⋅+⎢⎥⎢⎥⎣⎦⎣⎦∑∑()()()210.025120.97510.9750.975n n n n --⎡⎤=⨯+⨯++-⨯+⎣⎦,()()()()()()210.9750.02510.97520.97510.9750.975n n n E n n n n --⎡⎤⋅=⨯⨯++-⨯+-⨯+⎣⎦,两式相减得()()()()()2110.0250.02510.9750.97510.9750.0250.975n n n E n n n ---⎡⎤⋅=⨯+++--⨯+⨯⎣⎦ ,所以()()()10.9754010.97510.975nn E n -⎡⎤==-⎣⎦-,又由题意可得()5E n ≤,所以()4010.9755n ⎡⎤-≤⎣⎦,即()0.9750.875n ≥,注意到当5n =时,有50.9750.8810.875≈>,且当6n =时,有60.9750.8590.875=<;综上所述:n 的最大值为5.21.已知点A 为圆22:60C x y +--=上任意一点,点B 的坐标为(),线段AB 的垂直平分线与直线AC 交于点D .(1)求点D 的轨迹E 的方程;(2)设轨迹E 与x 轴分别交于12,A A 两点(1A 在2A 的左侧),过()3,0R 的直线l 与轨迹E 交于,M N 两点,直线1A M 与直线2A N 的交于P ,证明:P 在定直线上.【答案】(1)22146x y -=(2)证明见解析【解析】【分析】(1)根据题意推出||||||4DC DB -=,结合双曲线定义即可求得答案;(2)设出直线l 的方程,联立双曲线方程,得到根与系数的关系,表示出直线1A M 和2A N 的方程,推得122121522ty y y x x ty y y ++=-+,结合根与系数的关系化简,即可证明结论.【小问1详解】由22:60C x y +--=得22:(61C x y +=,其半径为4,因为线段AB 的垂直平分线与直线AC 交于点D,故||||DB DA =,则||||||||||||||4DC DB DC DA AC -=-==,而||84BC =>,故点D 的轨迹E 为以,B C 为焦点的双曲线,则22224,2,26a a c c b c a ====∴=-=,故点D 的轨迹E 的方程为22146x y -=.【小问2详解】证明:由题意知12(2,0),(2,0)A A -,若直线l 斜率为0,则其与双曲线的交点为双曲线的两顶点,不合题意;故直线l 的斜率不能为0,故设其方程为3x ty =+,联立223146x ty x y =+⎧⎪⎨-=⎪⎩,得22(32)18150t y ty -++=,21441200t ∆=+>,故12212218321532t y y t y y t -⎧+=⎪⎪-⎨⎪=⎪-⎩,设()()1122,,,M x y N x y ,则直线1A M 的方程为1111(2)(2)25y y y x x x ty =+=+++,直线2A N 的方程为2222(2)(2)21y y y x x x ty =-=--+,故122121522ty y y x x ty y y ++=-+,则2221221113232=531518755()523215152232t t y y x t t y t t t t t x y -+---+-=--+--=--+,即252x x +=--,解得43x =,故直线1A M 与直线2A N 的交点P 在定直线上.【点睛】难点点睛:本题考查了利用双曲线定义求解双曲线方程以及直线和双曲线的位置关系中的点在定直线上的问题,难点在于证明直线1A M 与直线2A N 的交点P 在定直线上,解答时要设直线方程,利用根与系数的关系进行化简,计算过程比较复杂,且大都是关于字母参数的运算,要十分细心.22.已知函数()()()ln 1,e 2ln 3ln23xf x xg x ax a =+=-++.(1)当()()1,00,x ∈-⋃+∞时,求证:()112f x x x >-+;(2)若()1,x ∈-+∞时,()()g x f x ≥,求实数a 的取值范围.【答案】(1)证明见详解(2)(0,【解析】【分析】(1)对()0,x ∈+∞与()1,0x ∈-进行分类讨论,通过导函数求单调性得出最值即可证明;(2)原式化简可得()e 2ln 3ln23ln 1x a a x x -+≥--,只需求得()()e ln 1x F x ax x =-+的最小值,最小值利用虚根0x 表示,再利用0x 置换a 从而得出0x 的不等式,构造函数()()()23ln 123ln 231xH x x x x =++++++求出()0H x ≥的解集,最后结合函数()00ln 2ln 1a x x =-+-的单调性即可求出a 的范围.【小问1详解】由题知,当()0,x ∈+∞时,原不等式可化为:()2ln 12x x x +>-+,令()()212ln x x h x x =++-,则()211011x h x x x x '=+-=>++,所以()h x 在()0,∞+上单调递增,从而有()()00h x h >=,故原不等式成立.当()1,0x ∈-时,原不等式等价于()0h x <,又()211011x h x x x x '=+-=>++,所以()h x 在()1,0-上单调递增,从而有()()00h x h <=,故原不等式成立.综上所述:当()()1,00,x ∈-⋃+∞时,恒有()112f x x x >-+.【小问2详解】由()e 2ln 3ln23xg x ax a =-++表达式可知0a >,()()g x f x ≥对()1,x ∈-+∞恒成立等价于()e 2ln 3ln23ln 1x a a x x -+≥--对()1,x ∈-+∞恒成立令()()e ln 1x F x ax x =-+,则有()()()1e e 1x x F x a x x '=+-+,令()()()()1e e 1x x G x F x a x x '==+-+,则有()()()212e 01x G x a x x '=++>+所以()F x '在()1,x ∈-+∞上单调递增又1x →-时,()F x '→-∞,x →+∞时()F x '→+∞从而存在唯一()01,x ∈-+∞,使得()00F x '=,即()()00001e e 01x x a x x +-=+,可得()()00001e e 1x x a x x =++,()00ln 2ln 1a x x =-+-,当()01,x x ∈-时,()00F x '<,()F x 在()01,x x ∈-单调递减,当()0,x x ∈+∞时,()00F x '>,()F x 在()0,x x ∈+∞单调递增,故()()()0000e ln 1xF x F x ax x ≥=-+故原不等式恒成立只需()()()00000020e ln 122ln 13ln 231e x x x x x x x ⋅-+≥-+---⎡⎤⎣⎦+即()()000203ln 123ln 2301x x x x +++++≥+,构造函数()()()23ln 123ln 231x H x x x x =++++++可得()()()()2331335422111xx x H x x x x -++'=++=++++()1x >-,当1x >-时,令()2354u x x x =++,因为2548230∆=-=-<从而可得()0H x '>在()1,x ∈-+∞时恒成立又102H ⎛⎫-= ⎪⎝⎭,所以()0H x ≥的解集为1,2⎡⎫-+∞⎪⎢⎣⎭.又因为()00ln 2ln 1a x x =-+-,令()()2ln 1m x x x =-+-,易得()m x 在定义域内单调递减,所以111ln 2ln 1ln 4222a ⎛⎫≤--++=+ ⎪⎝⎭所以1ln 42e a +≤=,故a 的取值范围为:(0,【点睛】思路点睛:(1)不等式两边同时去分母时务必要记得对分母的正负分类讨论;(2)恒成立问题可以优先转化为最值问题,而最值问题往往通过导函数作为工具;(3)隐零点的处理思路:第一步:用零点存在性定理判定导函数零点的存在性,其中难点是通过合理赋值,需要仔细观察式子多次尝试;第二步:虚设零点并确定取值范围,通过零点方程进行代换,可能需要进行多次.。
2024届湖南省永州市高三上学期第一次模拟考试全真演练物理试题(基础必刷)一、单项选择题(本题包含8小题,每小题4分,共32分。
在每小题给出的四个选项中,只有一项是符合题目要求的)(共8题)第(1)题下列说法正确的是( )A.光波与机械波一样,都有横波和纵波B.一切运动的宏观物体都没有波动性C.根据汤姆孙原子模型,在粒子散射实验中,大部分粒子穿过金箔后应该会有明显偏转D.理想气体分子间既无斥力又无引力第(2)题2024年1月11日,太原卫星发射中心将云遥一号卫星送入预定轨道,飞行试验任务取得圆满成功。
已知“云遥一号”在轨道做匀速圆周运动,运行周期为T,地球的半径为R,地球表面的重力加速度为g,引力常量为G,忽略地球自转的影响,下列说法正确的是( )A.地球的质量为B.“云遥一号”的轨道半径为C.“云遥一号”的线速度可能大于D.“云遥一号”的加速度可能大于g第(3)题2022年12月18日卡塔尔世界杯决赛在亿万球迷的欢呼声中落下帷幕,最终经过点球大战,阿根廷队以7∶5的成绩击败法国队夺得冠军。
关于足球运动,下列说法正确的是( )A.在研究香蕉球和电梯球的形成原因时,足球都可以被看成质点B.阻力作用下足球运动速度逐渐变小,说明力是改变物体运动状态的原因C.守门员用双手将足球以原速率扑出的过程,足球的动量、动能均保持不变D.罚点球过程中,运动员对足球的弹力越大,足球的动量变化越大第(4)题如图甲,A、B是某电场中的一条电场线上的两点,一带负电的粒子从点由静止释放,仅在静电力的作用下从点运动到点,其运动的图像如图乙所示。
取A点为坐标原点,且规定,方向为正方向建立轴,作出了所在直线的电场强度大小、电势、粒子的电势能,随位移的变化的图像、图像、图像,其中可能正确的是( )A.B.C.D.第(5)题如图所示在xOy平面内,x轴上的M点和的N点分别固定两个点电荷。
N处点电荷带正电,电荷量为q。
若规定无究远处电势为0,则以O为圆心,半径为2a的圆上各点电势均为0。
2024年永州市高三语文第一次模拟联考试卷试卷满分:150分考试时间:150分钟一、现代文阅读(35分)(一)现代文阅读I(本题共5小题,18分)材料一:在数千年的中国思想发展史中,我们几乎看不到从根本上把客观世界当作镜子来反观自己、发现自己、认识自己的努力,而总是看见把人的内心当作平静的湖水,认为真正的本心是“虚静”“无事”“空”。
中国人更多地用镜子来比喻人心而不是外界对象,镜子的作用不是用来认识自我,而是用来反映世界、“玄览”万物、呈现宇宙本体的,即是说。
镜子(人心)本身是看不见的,在镜子里看见的都是外界事物:人们从镜中反映的外界事物得知镜子的存在,但却不能把握那独立于一切外界事物的镜子实体的形象。
进入现代,我们热烈地讨论“自由”“人性”和“独立人格”,但看上去轰轰烈烈的时代思潮如果不涉及“人之镜”的根本颜倒,终将只是过眼烟云。
所谓根本的频倒是指:不再仅仅把人心看作被动而平静地反映外界的“明镜”,而是要能动地从外部世界中去获得自我的“确证”。
伟大的哲学家柏拉图通过“洞喻”,以理性贯通人性和对象世界,认为人只要运用他的“理性之光”反观自身,对自己的固有本性加以“回忆”(洞中囚徒回转头,发现了真实事物),就能触及并把握客观的世界本体。
从这里产生了西方哲学源远流长的“反思”学说。
“反思”(reflexion),也就是反映、反射,它与中国古代“吾日三省吾身”的那种反省不同,不是直接检查自己干净的心地上沾染了哪些灰尘,而是从对象上回过头来思索自己的本性。
中国传统的反省是以人的“心性”为出发点的,人心被假定为已知的、人人相同的、平静一色的,但这恰好使人心本身成了视觉上的一个“盲点”。
西方的反思则是从对象出发的,人心被看作有待于认知的,这就使得人不断地从外面转回头,不是为了“返本归原”,而是要对人性、人心做步步深入的探索。
这种从外向内不断深入的过程表明,人先要认识对象,然后才能认识自己,才能对自己的心性有真正的“自我意识”。
2024年湖南省永州市语文高三上学期模拟试题与参考答案一、现代文阅读Ⅰ(18分)阅读下面的文字,完成1~5题。
文题:《文化的传承与创新》文化,是一个民族的精神家园,是历史长河中积淀的智慧与情感的结晶。
它既是过去与现在的桥梁,也是连接个体与社会的纽带。
在全球化日益加深的今天,文化的传承与创新显得尤为重要。
(一)文化传承的价值文化传承,不仅仅是对古老习俗、传统艺术、经典文献等形式的简单复制,更是一种精神与智慧的传递。
它让我们在快速变化的现代社会中,能够找到归属感和身份认同。
正如春节的鞭炮声、中秋的团圆月,这些文化符号不仅承载着家族的记忆,更凝聚了民族的情感。
通过文化传承,我们得以理解自己的来路,从而更加坚定前行的方向。
(二)文化创新的必要性然而,文化传承并非一成不变。
在时代的洪流中,文化必须不断创新,才能保持其生命力和活力。
文化创新,是在尊重传统的基础上,融入现代元素,使传统文化以新的面貌和形式呈现给世人。
例如,京剧与现代科技的结合,不仅让古老的戏曲艺术焕发出新的光彩,也吸引了更多年轻人的关注和喜爱。
文化创新,是推动文化繁荣发展的重要动力。
(三)传承与创新的平衡文化传承与创新并非相互排斥,而是相辅相成、相互促进的。
没有传承,创新就失去了根基;没有创新,传承则可能陷入僵化。
因此,在文化传承与创新的道路上,我们需要找到一种平衡。
这种平衡,既要尊重传统,保持文化的连续性和稳定性;又要勇于创新,为传统文化注入新的活力和内涵。
只有这样,我们才能让文化之树常青,让民族精神生生不息。
(四)结语在全球化的今天,文化的传承与创新是每一个国家和民族都面临的重大课题。
让我们携手努力,共同守护好这份宝贵的文化遗产,让它在新的时代背景下焕发出更加璀璨的光芒。
1.下列关于“文化传承”的表述,不正确的一项是()A. 文化传承是民族精神的传递,是历史智慧的结晶。
B. 文化传承只是简单复制古老习俗、传统艺术和经典文献。
C. 文化传承有助于我们在现代社会中找到归属感和身份认同。
湖南省永州市2024届高三上学期第一次模拟考试语文试题及答案解析一、现代文阅读(35分)(一)现代文阅读I(本题共5小题,19分)阅读下面的文字,完成1~5题。
长期以来,对于中华传统文化的内涵特征存在着不同理解。
一些观点认为,中华文明属于大陆文明,中华传统文化以内陆文明为底色,与海洋关系不大。
这种观点的形成原因较为多样和复杂,西方文化思想的影响是一个重要来源。
黑格尔就提出东西方拥有不同文明体系的观点:以中国为代表的东方文化是内陆文化,是僵化和停滞的:以欧洲为代表的西方文化是海洋文化,是进取和创新的,这种文化的差异造成了人类文明形态的差异。
这种观点是片面的,不符合历史实际。
中华传统文化是开放包容的文化,是多元同构的文化,海洋文化是中华传统文化的重要特质。
中华传统文化具有陆地和海洋的双重品格,海洋特质是其鲜明的文化特征之一。
中国既有广袤的大陆,也有辽阔的海疆,各族人民在长期的生产生活实践中形成了悠久的海洋文化,这是中国古代历史与文化进程的一个重要组成部分。
中华传统文化的海洋特质孕育于远古时期,考古学家在周口店山顶洞人遗址中就发现了海蚌壳、海鱼骨等遗存。
先秦两汉时期,人们对海洋的认识与利用逐渐丰富和拓展。
秦始皇曾数次东巡,并派徐福率众东渡,这是我国历史上第一次大规模海上航行的明确记载。
《庄子》《山海经》等大量早期古代经典文献中也都不乏对海洋的描述,特别是刳木为舟、煮海为盐等记载,都是时人利用海洋的真实写照。
汉代则有了国人走向远海更为具体的文献记载,“海上丝绸之路”开始扬帆远航,贸易与交流东到日韩,南至东南亚各国。
六朝隋唐时期,对于海洋的探索与开发显著推进。
三国时期,造船技术进一步提升,魏国曾在青、究、幽、冀四州大造海船,当时东吴的造船业最为发达,船舶已经有了比较成熟的分隔舱技术,即使个别船舱受损进水也不影响航行。
据史料记载,孙权曾派遗船队进行了数次大规模海上远航,远至台湾、东南亚等地。
唐代不仅陆上疆域广阔,对于海洋的控制和影响也实现了空前拓展。
2024年湖南省永州市高三第一次模拟考试全真演练物理试题(基础必刷)学校:_______ 班级:__________姓名:_______ 考号:__________(满分:100分时间:75分钟)总分栏题号一二三四五六七总分得分评卷人得分一、单项选择题(本题包含8小题,每小题4分,共32分。
在每小题给出的四个选项中,只有一项是符合题目要求的)(共8题)第(1)题下列关于原子物理知识说法正确的是()A.甲图为氢原子的能级结构图,氢原子从基态跃迁到激发态时,放出能量B.乙图中重核裂变产生的中子能使核裂变反应连续的进行,称为链式反应,其中一种核裂变反应方程为C.丙图为光电效应中光电子最大初动能与入射光频率的关系图线,不同频率的光照射同种金属发生光电效应时,图线的斜率不相同D.两个轻核结合成质量较大的核,核子的比结合能增加第(2)题质量相等的均匀柔软细绳A、B平放于水平地面上,细绳A较长。
分别捏住两绳中点缓慢提起,使它们全部离开地面,两绳中点被提升的高度分别为、,上述过程中克服重力做的功分别为、。
以下说法正确的是()A.若,则一定有B.若,则可能有C.若,则可能有D.若,则一定有第(3)题如图所示,在倾角为的光滑绝缘斜面上固定一个挡板,在挡板上连接一根劲度系数为的绝缘轻质弹簧,弹簧另一端与A球连接。
A、B、C三小球的质量均为M,,,当系统处于静止状态时,三小球等间距排列。
已知静电力常量为k,则()A.B.弹簧伸长量为C.A球受到的库仑力大小为2MgD.相邻两小球间距为第(4)题如图所示,两个可视为质点的带同种电荷的小球a和b,放置在一个光滑绝缘半球面内,已知小球a和b的质量分别为m1、m2,电荷量分别为q1、q2,两球处于平衡状态时α<β.则以下判断正确的是A.m1>m2B.m1<m2C.q1>q2D.q1<q2第(5)题发射人造地球卫星时,火箭使卫星不断加速后以一定的速度进入预定轨道。
湖南省永州市2025届高三上学期第一次模拟考试数学试题一、单选题:本题共8小题,每小题5分,共40分。
在每小题给出的选项中,只有一项是符合题目要求的。
1.设A={x|x2−4x−5=0},B={x|x2=1},则A∪B=( )A. {−1,1,5}B. {−1,1,−5}C. {−1}D. {1}2.复数2i−1的共轭复数是( )A. i−1B. i+1C. −1−iD. 1−i3.已知|a|=3,|b|=4,且a与b不共线,则“向量a+kb与a−kb垂直”是“k=34”的( )A. 充分不必要条件B. 必要不充分条件C. 充要条件D. 既不充分也不必要条件4.函数f(x)=x2+ln x在点(1,1)处的切线方程是( )A. 3x−y−2=0B. 2x−y−2=0C. 3x+y−2=0D. 2x+y−2=05.已知函数f(x)=cos2(ωx+π6)(ω>0)的最小正周期为π,则f(x)的对称轴可以是( )A. x=π24B. x=π12C. x=π6D. x=π36.在2024年巴黎奥运会中,甲、乙、丙、丁、戊5人参与接待、引导和协助三类志愿者服务工作,每类工作必须有志愿者参加,每个志愿者只能参加一类工作,若甲只能参加接待工作,那么不同的志愿者分配方案的种数是( )A. 38B. 42C. 50D. 567.已知数列{a n}满足a n+1−a na n=a n+2−a n+1a n+2(n∈N∗),且a1=1,a2024=22025,则a1a2+a2a3+⋯+a n a n+1=( )A. n2n+1B. nn+2C. 2n2n+1D. 2nn+28.已知函数f(x)=ln|a+11−x|+b+x4(a,b∈R)为奇函数,且f(x)在区间(m,m2)上有最小值,则实数m的取值范围是( )A. (3,3)B. (2,2)C. (2,3)D. (2,3)二、多选题:本题共3小题,共15分。
2024年湖南省永州市高三第一次模拟考试全真演练物理试题(基础必刷)一、单项选择题(本题包含8小题,每小题4分,共32分。
在每小题给出的四个选项中,只有一项是符合题目要求的)(共8题)第(1)题新一代地球同步轨道通信卫星中星6D于2022年4月15日由长征三号乙增强型运载火箭在中国西昌卫星发射中心发射成功,在今年杭州亚运会上确保了开幕式直播保障工作万无一失。
关于中星6D卫星,下列说法中不正确的是()A.运行轨道的高度是确定的B.可能出现在北京的正上方C.围绕地球转动的方向一定是自西向东D.运行速率小于第一宇宙速度第(2)题晾晒衣服的绳子两端A、B分别固定在两根竖直杆上,A点高于B点,原来无风状态下衣服保持静止。
某时一阵恒定的风吹来,衣服受到水平向右的恒力而发生滑动,并在新的位置保持静止(如图),不计绳子的质量及绳与衣架挂钩间的摩擦,下列说法中一定正确的是( )A.有风时,挂钩左右两侧的绳子拉力不相等B.无风时,挂钩左右两侧绳子OA较陡C.相比无风时,有风的情况下∠AOB大D.在有风的情况下,A点沿杆稍下移到C点,绳子的拉力变小第(3)题如图所示,水平细杆上套一细环A,环A和球B间用一轻质绳相连,质量分别为m A、m B (m A>m B),由于B球受到水平风力作用,A环与B球一起向右匀速运动,已知细绳与竖直方向的夹角为θ,则下列说法正确的是A.风力增大时,轻质绳对B球的拉力保持不变B.风力增大时,杆对A环的支持力保持不变C.B球受到的风力F为m A g tan θD.A环与水平细杆间的滑动摩擦因数为第(4)题把多匝小线圈和灵敏电流计串联后用于检测家装时隐藏在墙体内的导线是否通电,如图(a)所示。
墙体内有两根套了管的长导线AB、CD,AB水平,CD竖直,如图(b)所示。
检测时线圈平行墙面,当沿水平方向A1B1快速移动线圈时,电流计指针不偏转;当沿竖直方向C1D1方向快速移动线圈时,电流计指针偏转,则检测的结果是()A.两根导线中都有电流B.两根导线中都无电流C.AB中无电流,CD中有电流D.AB中有电流,CD中无电流第(5)题某灯光音乐喷泉运行时,五彩斑斓,景色蔚为壮观。
永州市2013年高考第一次模拟考试试卷英语命题人:陈清祥(宁远一中) 张忠良(祁阳一中) 田泽祥(江永一中) 李琼玲(江华一中)审题人:唐竹生(市教科院)时量:120分钟分值:150分注意:本试卷分为四个部分,包括听力、语言知识、阅读理解和书面表达。
答题前,考生须将答题卷密封线内的各项内容填写清楚,所有答案按要求正确清晰地填写在答题卷上。
考试结束后,将本试卷和答题卷一并交回。
Part I Listening Comprehension (30 marks)Section A (22.5 marks)Directions: In this section, you will hear six conversations between two speakers. For each conver sation, there are several questions and each question is followed by three choices marked A, B and C. List en carefully andthenchoose the best answer for each question.You will hear each conversation TWICE.Example:When will the magazine probably arrive?A. Wednesday.B. Thursday.C. Friday.The answer is B.Conversation 11. What has the weather been like these days?A. Windy.B.Sunny.C. Rainy.2. What will the temperature be tomorrow?A. 8℃.B. 10℃.C. 12℃.Conversation 23. Who is visiting the woman for the weekend?A. Her teacher.B. Her student.C. Her brother.4. How does the woman know Ann?A. She has just been introduced to her.B. She has taken piano lessons from her.C. They have met at a party before.Conversation 35. When did the man finish running every day last term?A. At 7:00.B. At 7:30.C. At 8:10.6. What does the woman think of his university life?A. Too dull.B. Just so so.C. Very great. Conversation 47. Where are the two speakers?A. In a library.B. In a bookstore.C. In an office.8. Why didn’t the woman lend him the three books?A. Because they are expensive.B. Because they are very important.C. Because they are single copies.9. How many books did the man finally take away?A. One.B. Three.C. Four.Conversation 510. What’s the relationship between the two speakers?A. Ticket seller and passenger.B. Saleswoman and customer.C. Close friends.11. Which flight is the man going to take?A. The early morning flight.B. The mid-morning flight.C. The early afternoon flight.12. Where does the conversation most probably take place?A. At the bus station.B. At the ticket office.C. At the city centre.Conversation 613. What was the woman’s first job?A. Sales assistant.B. Sales manager.C. Sales representative.14. Why did the woman give up the job?A. To travel with her friends.B. To prepare for her exams.C. To attend a meeting.15. Where did the woman stay?A. In England.B. In America.C. In Ireland.Section B (7.5 marks)Directions: In this section, you will hear a short passage. Listen carefully and then fill in the numb ered blanks with the information you have heard. Fill in each blank with NO MORE THAN THR EE WORDS.You will hear the short passage TWICE.Newspapers in BtitainTypes ● Serious newspapers: on happenings both 16 and abroad.● 17 newspapers: on entertainment.The Times ● Beginning in 18 .● Enjoying a good reputation for believable news and serious opinions.● Not giving its 19 to a political party.● Talking about new fashions and 20 of the young people occasionally.Part II Language Knowledge (45 marks)Section A (15 marks)Directions: Beneath each of the following sentences there are four choices marked A,B, C and D. Choose the one answer that best completes the sentence.Example:The wild flowers looked like a soft orange blanket the desert.A. coveringB. coveredC. coverD. to coverThe answer is A.21. Tom took a taxi to the high-speed train station, only his train had just left.A. findingB. to findC. foundD. find22. Food supplies in the tsunami-stricken area . We must act immediately before there’s none l eft.A. have run outB. run outC. ran outD. are running out23. Though to see us, the professor gave us a warm welcome.A. surprisingB. surprisedC. to surpriseD. being surprised24. Tom has always been working hard. , he will hopefully achieve good grades in the coming test.A. HoweverB. OtherwiseC. ThereforeD. Besides25. Lily in a top school in Changsha, but she is studying in our school now.A. studiesB. will studyC. has studiedD. studied26. Mo Yan had been awarded the Nobel Prize for Literature made us Chinese proud.A. WhatB. WhichC. ThatD. Whether27. People will keep fit if they to eat more fruit and vegetables.A. persuadeB. will persuadeC. will be persuadedD. are persuaded28. I was feeling left out in the new school Alice, an easygoing girl from Canada, came to sta y with me.A. asB. onceC. whenD. while29. We lost our way in the forest park, otherwise we more places of interest yesterday.A. visitedB. had visitedC. would visitD. would have visited30. Only after we have gone through hard times something to be grateful for.A. will we understandB. we will understandC. we understoodD. did we understand31. Most riders of electric bikes in China 40-50 kilometers per hour often ignore red lights.A. reachingB. reachedC. to reachD. to have reached32. difficulties we may meet with in our life, we should keep a positive attitude towards life.A. HoweverB. WhateverC. WhicheverD. Whenever33. — Mum, I really think Dad should have a break and get relaxed.— Yes. He too long.A. has been readingB. readC. had readD. is reading34. The driver from that bus company, was extremely calm and brave in face of danger, saved all the passengers on board.A. whichB. whoC. whomD. that35. Joe, along with his friends bound to find nobody there, for the rest gone for their lunch.A. is; haveB. is; hasC. are; haveD. are; hasSection B (18 marks)Directions: For each blank in the following passage there are four words or phrases marked A, B, C and D. Fill in each blank with the word or phrase that best fits the context.It was a warm sunny Saturday afternoon about fifteen years ago. I offered to take my 36to the local playground. As soon as we got there, my daughter headed for the 37 and asked fo r a push. As I was helping my daughter to 38 higher and higher, I noticed another little girl tryin g in vain to get her own swing(秋千) going. Her elderly grandmother was sitting quietly on a near by bench and smiled at me.I walked over to the little girl and 39 if she could use a push, too. She smiled and answered “Ye s!” I soon had her feet flying towards the clouds while she laughed happily. For the next two hour s I found myself 40 swings and playing games with my daughter and the little girl. By the tim e we headed home, I was 41 worn out, but my spirits were still flying higher than those swing s.Two years later, after a long day’s work I went to 42 my kids from the local grade school. 4 3 , I stood in the parents’ waiting area waiting for my children. Suddenly, I felt two tiny arms aro und my stomach. I looked down and there was the little girl from the playground smiling up at m e. She gave me one more big hug before 44 to catch her school bus. As I watched her back, I di dn’t feel quite so tired any more and my 45 were once again rising in the Heavens.In this life,every single bit of love we 46 finds its way back to us again. It may take seconds o r it may take years. The law of love, though, is never broken. The love we share, the kindness we give and the 47 we create will always come back to bless us.36. A. daughter B. friend C. mother D. student37. A. balls B. flowers C. swings D. crowds38. A. lift B. go C. climb D. jump39. A. asked B. wondered C. saw D. doubted40. A. taking B. shaking C. making D. pushing41. A. mentally B. simply C. physically D. mostly42. A. pick up B. send for C. look after D. see off43. A. Excited B. Surprised C. Satisfied D. Tired44. A. putting off B. looking around C. showing up D. heading off45. A. thoughts B. spirits C. memories D. feelings46. A. seek B. share C. imagine D. face47. A. beauty B. idea C. happiness D. valueSection C (12 marks)Directions: Complete the following passage by filling in each blank with one word that best fits th e context.Travel is a very good activity. When traveling, you can relax 48 , forget your tiredness or trouble s, and have the energy to take on the new tasks waiting for you.But sometimes traveling is 49 an enjoyable thing. For example, the weather can be changeabl e. 50 you climb a mountain, it may rain suddenly. You may be caught 51 the rain and may cat ch a cold. The worst thing is that you may have your money stolen 52 you may have an injur y. All these terrible things are 53 can happen to you.Therefore, when you are to go on a trip, you 54 make a good preparation. Firstly, you must hav e clear information about the weather. Secondly, you should choose 55 good companion so tha t you can help each other. Thirdly, you must be careful enough and try to avoid accidents. If you d o this, you will surely enjoy your travel.Part III Reading Comprehension (30 marks)Directions: Read the following three passages. Each passage is followed by several questions or unfinished statements. For each of them there are four choices marked A, B,C and D. Choose the o ne that fits best according to the information given in the passage.ADo you have any skiing equipment you no longer need? A ski school in the far north of India coul d put it to good use.In March we published a photo story about the extraordinary Zsnskar region in northern India,wh ich is cut off from the outside world for more than seven months of the year,and only accessible v ia a frozen river.We also included information about the limited use of skiing in the region and th e recent creation of the Zanskar Ski School:“Despite the difficulties of travelling through the region when the snow comes,skiing hasn’t tradi tionally been used as a means of transport by the locals,largely because trees don’t grow here, so t here is little in the way of raw materials from which to make skis.In 1995, a group of British scie ntists in the region noticed the lack of skis and one of them returned to set up the Zanskar Ski Sch ool in Padam.The school provides lessons for a small fee and rents skis to the local people. Amo ng the benefits that the school hopes to bring are improved education — children often find it diffi cult to get to school through the deep snow — and the possibility of offering ski tours to tourists i n the future.So far,more than 300 local people have received training,and local doctors and p olicemen regularly borrow skis.”But what we weren’t able to include in the article is that the ski school is always on the look out fo r old skiing equipment — particularly of a size suitable for children — and, I thought. Now the Eu ropean ski season is drawing to a close,there might be a few of you out there who have some old e quipment you’d like to see go to a good home.If that’s the ease you can get in touch with the sch ool via their website www.zanskarski .56. What’s the purpose in writing the text?A. To ask people to give away their skis to the school.B. To attract more tourists to the area.C. To appeal to more locals to attend the school.D. To raise money to develop this area.57. The local people don’t use skiing to go about because .A. it is against the local customB. trees are in the way of the skiing routeC. they don’t have the wood to make skisD. it is dangerous to go skiing in this region58. The Zanskar Ski School .A. has donated money to the local communityB. makes it easier for the students to attend schoolC. provides special training to the touristsD. has borrowed many skis from Europe59. Who would be the most helpful to the school now?A. Locals in Zanskar region.B. Students in the Zanskar Ski School.C. People having old skiing equipment.D. Tavellers enjoying skiing.60. What can be the best title for the text?A. An extraordinary region in India.B. A popular sport-skiing.C. A good means of transport.D. A home for old skis.BHow do you know if your home is an easy aim for thefts? Around the holidays, many families do n’t consider taking proper measures to prevent their homes from suffering holiday thefts.With jus t a few simple steps, you can better make sure of the safety of your home during all of the holida y celebrations.Here are a few tips for making it difficult to tell you are away from home.●Either have a trusted neighbor pick up your mail and newspapers, or tell your mailperson to hold your mail until you return.Nothing says “Hey, we are not home!” like when your postbox is fill ed with all kinds of mails and you have many different newspapers in your driveway.●Set several different lights in your house on random timers(随机定时器).Don’t leave your o utdoor lights on all the time.Instead, put your outside lights on timers to be on during the nights.If an outdoor light remains on for days at a time it means that nobody is home to turn it off.●If you have pets that you are not taking with you on vacation, leave them with a friend, rather tha n having someone come into your house every day to take care of them.When thefts see a neighb or or friend entering your house every day, they will know you are not home.●Close all your curtains when you leave town. This is effective to deter possible thefts, as no one can see what is in your house. If they don’t know what is inside, then they are less likely to run t he risk of breaking in.This article just has suggested a few tips to help you keep your house safe while you are on holida y.Nothing can truly protect your home unless you have it monitored by a professional home secu rity system.61.What is the main idea of the passage?A. To tell us how to prevent the thefts around the holidays.B. To let the outdoor lights on all the time.C. To tell us many families suffering from the thefts while they are on holiday.D. To tell you to have your neighbor go to your house to take care of your pet.62.If you are on holiday in other places, the lights in your house should .A. be turned on only once one dayB. be kept on all the nightC. be replaced by random timersD. be lit in an irregular way63.To make your home truly protected, what does the writer advise you to do?A. Have all the curtains closed.B. Stop your mail service at once.C. Turn to your close neighbors or friends.D. Equip your home with a security system. 64.Most of the tips mentioned in the text seem to .A. be very popular with familiesB. have no effect on preventing theftsC. give a false impression on theftsD. be a little hard to be brought into effect65.The underlined word " deter " probably means “”.A. discoverB. discourageC. surpriseD. attractCFood sometimes gets poisoned with harmful things. A person who eats such food can get an illnes s called food poisoning. Food poisoning is usually not serious, but some types are deadly. The sy mptoms of food poisoning usually begin within hours of eating the poisoned food. Fever is one o f the most common symptoms.Certain microorganisms(微生物)cause most types of food poisoning. Bacteria and other microo rganisms can poison eggs, meat, vegetables, and many other foods. After entering the body, these t iny living things release poisons that make people sick.Some chemicals can also cause food poisoning. They are often added to food while it is being gro wn, processed, or prepared. For example, many farmers spray chemicals on crops to kill weeds an d insects. Some people may have a bad reaction to those chemicals when they eat the crops. Some plants and animals contain natural poisons that are harmful to people. These include certai n kinds of seafood, grains, nuts, seeds, beans, and mushrooms.When people handle food properly, the risk of food poisoning is very small. Microorganisms multi ply rapidly in dirty places and in warm temperatures. This means that people should never touch f ood with dirty hands or put food on unwashed surfaces. Food should be kept in a refrigerator to st op microorganisms from growing. Meat needs to be cooked thoroughly to kill any dangerous micr oorganisms. People should also wash food covered with chemicals before eating it. Finally, peopl e should not eat wild mushrooms or other foods that grow in the wild. Some of these foods may co ntain natural materials that are poisonous to humans. In addition, some types of fish can be poison ous.Most people recover from food poisoning after a few days of resting and drinking extra water. If people eat natural poisons, they must go to the hospital right away to have their stomachs emptied.66. Which of the following statements is NOT true?A. Food poisoning means death.B. Food when poisoned can make people sick.C. Food poisoning comes in varieties.D. Food poisoning can be serious.67. We know from the passage that the symptoms of food poisoning .A. are only accompanied by a feverB. are too common to be noticedC. can he ignoredD. can be noticed within hours68. Food poisoning can be caused by all the following EXCEPT .A. low temperaturesB. some chemicalsC. some tiny living thingsD. certain natural materials69. From Paragraph 5, we can learn that .A. mushrooms should not be eatenB. different types of food should be handled differentlyC. vegetables are safer than meat and seafoodD. natural poisons are more dangerous than chemicals70. It can be inferred from the passage that .A. natural materials are safe in food processingB. chemicals are needed in food processingC. food poisoning can be kept under controlD. food poisoning is out of controlPart IV Writing (45 marks)Section A (10 marks)Directions: Read the following passage. Fill in the numbered blanks by using the information fro m the passage.Write NO MORE THAN THREE WORDS for each answer.Children are used to the parties that consist of junk food, loud music and the like. However, today’s environmental condition is serious, so to save our environment, we need to do our bit by makin g small changes in our activities like planning our kid’s birthday parties in an eco-friendly manne r.The first idea for the “green” birthday party is selecting a “green” location. You can put some choi ces in front of your child like gardens, parks and farms and let him or her select one for the part y. The benefit of choosing a natural outdoor locations is that it doesn’t require much decoration, w hich will save your money. Also, it’ll bring your child close to nature.Secondly, go “green” while you’re listing out the required materials for the party. Use reusable an d recyclable materials like cloth table covers instead of plastic. For decorations, avoid plastic by u sing natural things like plants, candles, etc. What’s more, you can avoid using paper invitations an d invite people by sending e-mail invitations to them.Thirdly, plan the food according to the “green” theme. Serve the delicious but healthy food to th e guests. Fruit, vegetables and nuts can be the most appropriate parts in party food as they taste gre at, and are extremely healthy. Home-made cakes will also serve the purpose very well.Lastly, conduct “green” activities. For giving children a learning experience, take them on a trip t o the nearest farm and let them see the working system there. After the learning experience, let the m play together in a park. Also children can make up stories which you can write down for them. These written pages will be colored by the kids and will be their return gifts.Plan a unique but wonderful birthday party for your kid to enjoy. If we all contribute to this caus e, soon we’ll see our earth back in her green coat.Title: 71 for Our KidsI. ReasonWe need to save our environment due to today’s 72 environmental condition.II. 73●Selecting a “green” locationAllowing children to 74 the location.Enabling to children to get close to nature.●Using“green” materialsUsing 75 materials.Avoiding paper invitations.76 e-mail invitations.●Planning 77Serving delicious but healthy food.● 78 “green” activitiesTaking children to a farm or park to 79 .Writing down stories by children.III. 80Planning a unique but wonderful birthday party helps save the earth.Section B (10 marks)Directions: Read the following passage. Answer the questions according to the information given i n the passage.Brazil has become one of the developing world’s great successes at reducing population growth — but more by accident than design. While countries such as India have made joint efforts to re duce birth rates, Brazil has had better result without really trying, says George Martine at Harvar d.Brazil’s population growth rate has dropped from 2.99% a year between 1951 and 1960 to 1.93% a year between 1981 and 1990, and Brazilian women now have only 2.7 children on averag e. Martine says this figure may have fallen still further since 1990, an achievement that makes it th e envy of many other Third World countries.Martine puts it down to among other things, soap operas and installment(分期付款)plans introd uced in the 1970s.Both played an important, although indirect, role in lowering the birth rate. Bra zil is one of the world’s biggest producers of soap operas. Globo, Brazil’s most popular televisio n network, shows three hours of soaps six nights a week, while three others show at least one hou r a night. Most soaps are based on wealthy characters living the high life in big cities.“Although they have never really tried to work in a message towards the problems of Reproductio n(生育), they describe middle and upper class values: not many children, different attitudes tow ards sex, women working, ” says Martine.“They sent this image to all parts of Brazil and made p eople conscious of other patterns of behavior and other values, which were put into a very attractiv e package.”Meanwhile, the installment plans tried to encourage the poor to become consumers.“This led to a n enormous change in consumption patterns and consumption was incompatible(不相容的) with unlimited reproduction, ” says Martine.81. How has Brazil cut back its population growth? ( No more than 6 words ) (2 marks)82. What are the two main factors in helping Brazil lower its birthrate? ( No more than 8 words ) (2 marks)83. What changes have soap operas brought to Brazilians since the 1990s? ( No more than 14 wor ds ) ( 3 marks )84. What is the passage mainly about? ( No more than 12 words ) ( 3 marks )Section C (25 marks)Directions: Write an English composition according to the instructions given below in Chinese. 在生活中,人与人之间难免会发生不愉快的事情,其中有误会,有矛盾,有争吵……请就此写一篇英语短文。