北京航空航天大学北航2015年春《会计学原理》在线作业二满分答案

北航《算法与数据结构》在线作业二一、单选题：1.若线性表最常用的操作是存取第i个元素及其前趋的值，则采用( )存储方式节省时间。

(满分:4)A. 单链表B. 双链表C. 单循环链表D. 顺序表正确答案:D2.除了( ) ，其它任何指针都不能在算法中作为常量出现，也无法显示。

(满分:4)A. 头指针B. 尾指针C. 指针型变量D. 空指针正确答案:D3.栈的插入和删除操作在( )进行。

(满分:4)A. 栈顶B. 栈底C. 任意位置D. 指定位置正确答案:A4.采用分块查找时,若线性表中共有625个元素,查找每个元素的概率相同,假设采用顺序查找来确定结点所在的块时,每块应分( )个结点最佳(满分:4)A. 10B. 25C. 6D. 625正确答案:B5.图的深度优先遍历类似于二叉树的( )。

(满分:4)A. 先序遍历B. 中序遍历C. 后序遍历D. 层次遍历正确答案:A6.计算机的算法是( )。

(满分:4)A. 计算方法B. 排序方法C. 对特定问题求解步骤的一种描述D. 调度算法正确答案:C7.以下四种排序方法中，要求附加的内存容量最大的是( ) (满分:4)A. 插入排序B. 选择排序C. 快速排序D. 归并排序正确答案:D8.对于顺序表，以下说法错误的是( ) (满分:4)A. 顺序表是用一维数组实现的线性表，数组的下标可以看成是元素的绝对地址B. 顺序表的所有存储结点按相应数据元素间的逻辑关系决定的次序依次排列C. 顺序表的特点是正确答案:A9.二叉树第i层上至多有( )结点。

(满分:4)逻辑结构中相邻的结点在存储结构中仍相邻D. 顺序表的特点是正确答案:D10.深度为6（根的层次为1）的二叉树至多有( )结点。

(满分:4)逻辑上相邻的元素，存储在物理位置也相邻的单元中正确答案:D11.假设一个有n个顶点和e条弧的有向图用邻接表表示,则删除与某个顶点vi相关的所有弧的时间复杂度是( )。

(满分:4)A. 2iB. 2的i次方C. 2i-1D. 2 的（i-1）次方正确答案:C12.从一棵B树删除元素的过程中，若最终引起树根结点的合并，则新树高度是( )。

2015春北京航空航天大学《发动机II》在线作业二及答案北航《发动机II》在线作业二单选题多选题判断题一、单选题（共4道试题，共16分。

）1.不加入能量而能够不断做功的机器不存在的理论基础是（）A.热力学第一定律B.热力学第二定律C.质量守恒定律-----选择：A2.关于发动机参数指示两种说法：1）性能指示，也称主要指示；2）系统指示，称为次要指示，正确的是（）。

A.1）正确B.2）正确C.1）、2）均正确-----选择：C3.离心式压气机叶轮分为单面叶轮和双面叶轮两种。

关于双面叶轮有以下说法：1）从两面进可以增大进气量；2）对于平衡作用在轴承上的轴向力也有好处。

A.1）正确B.2）正确C.1）、2）均正确-----选择：C4.关于开环控制有以下两种说法：1）具有及时、稳定的优点；2)具有不能补偿所有干扰，精度差的缺点。

A.1)正确B.2）正确C.1）、2）均正确-----选择：C北航《发动机II》在线作业二单选题多选题判断题二、多选题（共10道试题，共40分。

）1.加力燃烧室的构成部分有（）A.扩压器B.火焰稳定器C.输油圈及燃油喷嘴D.点火装置和加力燃烧室壳体-----选择：ABCD2.发动机进气道的基本要求有（）A.保证空气量供给并使迎面气流损失小B.气流以均匀速度和压力进入压气机C.各种状态和范围的稳定工作-----选择：ABC3.航空推进系统按其组成和工作原理分为（）A.直接反作用推进系统B.间接反作用推进系统C.其它-----选择：AB4.可控的造型方法有哪几类（）A.反问题方法B.正问题迭代法C.反问题混合法-----选择：ABC5.影响发动机推力的因素有（）A.空气流量B.气体流过发动机时速度的增量C.发动机效率-----选择：AB6.压气机防喘振措施包括（）A.放气机构B.进口可转导流叶片和变弯度导流叶片C.多级可调静子叶片D.机匣处理和多转子压气机-----选择：ABCD7.燃气涡轮发动机的主要部件有（）A.进气装置B.压气机C.燃烧室D.涡轮和尾喷管-----选择：ABCD8.航空燃气涡轮发动机的主要性能参数有（）A.推力和推重比B.耗油率C.增压比和涵道比D.涡轮前燃气温度-----选择：ABCD9.压气机的主要损失有（）A.摩擦损失B.分离损失C.对涡损失D.漏气损失-----选择：ABCD10.排气装置有（）等组成。

北京航空航天大学2015春《航空英语2》在线作业二满分答案15春北航《航空英语2》在线作业二满分答案北航《航空英语2》在线作业二单选题一、单选题（共 25 道试题，共 100 分。

）1.My grandfather had always taken a ()interest in my work, and I had an equaladmiration for the stories of his time.A.splendidB.weightyC.vagueD.keen-----------------选择：D2. As one of the world’s highest paid models, she had her face () for five milliondollars.A.depositedB.assuredC.measuredD.insured-----------------选择：D3. We have arranged to go to the cinema on Friday, but we can be () and go anotherday.A.reliableB.probableC.feasibleD.flexible-----------------选择：D4. It’s very () of you not to talk aloud while the baby is asleep.A.concernedB.carefulC.considerableD.considerate-----------------选择：D5. Many in the credit industry expect that credit cards will eventually () papermoney for almost every purchase.A.exchangeB.reduceC.replaceD.trade-----------------选择：C6. The chairman was blamed for letting his secretary () too much work last week.A.take toB.take outC.take awayD.take on-----------------选择：D7. () the enormous flow of food from the entire globe, these countries have for manyyears not felt any population pressure.A.Thanks toB.By means ofC.In line withD.With regard to-----------------选择：A8. Louis Herman, at the University of Hawaii, has () a series of new experiments inwhich some animals have learned to understand sentences.A.installedB.equippedC.devisedD.formatted-----------------选择：C9. The little girl was so frightened that she just wouldn’t () her grip on my arm.A.loosenB.removeC.relieveD.dismiss-----------------选择：A10. The university has launched a research center to develop new ways of () bacteriawhich have become resistant to drug treatments.A.regulatingB.haltingC.interruptingbating-----------------选择：D11. I must congratulate you () the excellent design of the new bridge.A.withB.ofC.atD.on-----------------选择：D12. Every culture has developed () for certain kinds of food and drink, and equallystrong negative attitudes toward others.A.preferencesB.expectationsC.fantasiesD.fashions-----------------选择：A13. Last night he saw two dark () enter the building, and then there was theexplosion.A.featuresB.figuresC.sketchesD.images-----------------选择：B14. To speed up the () of letters, the Post Office introduced automatic sorting.A.treatmentB.deliveryC.transmissionD.departure-----------------选择：B15. We don’t know why so many people in that region like to wear dresses of such ()colors.A.lowB.humbledD.dull-----------------选择：D16. A word processor is much better than a typewriter in that it enables you to enterand () your text more easily.A.registerB.editC.proposeD.discharge-----------------选择：B17. John cannot afford to go to university, () going abroad.A.nothing butB.anything butC.not to speak ofD.nothing to speak of-----------------选择：C18. Researchers at the University of Illinois determined that the () of a father canhelp improve a child’s grades.A.involvementB.interactionC.associationmunication-----------------选择：A19. It may be necessary to stop () in the learning process and go back to the difficultpoints in the lessons.A.at a distanceB.at intervalsC.at caseD.at length-----------------选择：B20. Politically these nations tend to be (), with very high birth rates but pooreducation and very low levels of literacy.A.unstableB.reluctantC.rationalD.unsteady-----------------选择：A21. Three university departments have been () $600,000 to develop good practice inteaching and learning.A.promotedB.includedC.securedD.awarded-----------------选择：D22. There has been a collision () a number of cars on the main road to town.posingB.consistingC.involvingD.engaging-----------------选择：C23. Critics believe that the control of television by mass advertising has () thequality of the programs.A.lessenedB.declinedC.affectedD.effected-----------------选择：C24. Mrs. Smith was so () about everything that no servants could please her.A.specificB.specialC.preciseD.particular-----------------选择：D25. It is said in some parts of the world, goats, rather than cows, serve as a vital () ofmilk.A.storageB.sourceC.reserveD.resource-----------------选择：B-END-。

北航《微积分(上)》在线作业三一、单选题：1.函数y=|x-1|+2的极小值点是( ) (满分:6)A. 0B. 1C. 2D. 3正确答案:B2.设函数f(x)=x(x-1)(x-3)，则f ＇( 0 ) =( ) (满分:6)A. 0B. 1C. 3D. 2正确答案:C3.下列函数中( )是奇函数(满分:6)A. xsinxB. x+cosxC. x+sinxD. |x|+cosx正确答案:C4.设f(x)=e^(2+x),则当△x→0时，f(x+△x)-f(x)→( ) (满分:6)A. △xB. e2+△xC. e2D. 0正确答案:D5.集合B是由能被3除尽的全部整数组成的，则B可表示成(满分:6)A. {3，6，…，3n}B. {±3，±6，…，±3n}C. {0，±3，±6，…，±3n…}D. {0，±3，±6，…±3n}正确答案:C二、多选题：1.函数的左导数和右导数都存在，是函数在该点可导的充要条件(满分:7)A. 错误B. 正确正确答案:A2.对函数y=2008+x-sinx求导可得y′=1-cosx (满分:7)A. 错误B. 正确正确答案:B3.一元函数可导的充要条件是左右导数都存在且相等。

(满分:7)A. 错误B. 正确正确答案:B4.y=tan2x 是一个增函数(满分:7)A. 错误B. 正确正确答案:A5.函数的微分形式总是保持不变的性质叫微分的一阶形式不变性。

(满分:7)A. 错误B. 正确正确答案:B6.罗尔定理的几何意义是：一条两个端点的纵坐标相等的连续光滑曲线弧上至少有一点C （ξ，f(ξ)），曲线在C点的切线平行于x轴(满分:7)A. 错误B. 正确正确答案:B7.若直线y=3x+b为曲线y=x2+5x+4的切线,则b = 3 (满分:7)A. 错误B. 正确正确答案:B8.隐函数的导数表达式中不可含有y。