慕课标签存档

01 女性生殖系统解剖、生理

女性生殖系统解剖、生理测验

1、单选题：
‎有关月经的叙述，下列哪项是错误的？​
选项：
A: 不排卵也有月经来潮
B: 月经周期提前或延后7天左右属正常范围
C: 月经周期的长短，决定于增生期
D: 月经血一般是不凝的
E: 月经周期是指此次月经干净日至下次月经干净日
答案: 【 月经周期是指此次月经干净日至下次月经干净日】点我阅读全文

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2.有效市场假说及其缺陷

有效市场假说的测试

1、单选题：
‍支持有效市场假说成立的三个理论假定中，最重要的是哪一条？‍
选项：
A: 理性人假设
B: 噪音交易者的交易可相互抵消
C: 套利交易者的作用
D: 以上皆不是
答案: 【 套利交易者的作用】点我阅读全文

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第九章中西艺术

单元测验

1、单选题：
‎Which of the following does not belong to “the three friends in winter”?‌
选项：
A: orchid
B: pine
C: bamboo
D: plum
答案: 【 orchid】点我阅读全文

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Lesson2

Scanning

1、单选题：
‍Read the passage "The Discovery of X-rays" quickly and choose the paragraph(s) which contain(s) the answer(s). You may choose more than one answer for question 3. ‎‍‎The Discovery of X-rays‎‍ ‎Par. 1 Except for a brief description of the Compton effect, and a few other remarks, we have postponed the discussion of X-rays until the present chapter because it is particularly convenient to treat X-ray spectra after treating optical spectra. Although this ordering may have given the reader a distorted impression of the historical importance of X-rays, this impression will be corrected shortly as we describe the crucial role played by X-rays in the development of modern physics.‎Par. 2 X-rays were discovered in 1895 by Roentgen while studying the phenomena of gaseous discharge. Using a cathode ray tube with a high voltage of several tens of kilovolts, he noticed that salts of barium would fluoresce when brought near the tube, although nothing visible was emitted by the tube. This effect persisted when the tube was wrapped with a layer of black cardboard. Roentgen soon established that the agency responsible for the fluorescence originated at the point at which the stream of energetic electrons struck the glass wall of the tube. Because of its unknown nature, he gave this agency the name X-rays. He found that X-rays could manifest themselves by darkening wrapped photographic plates, discharging charged electroscopes, as well as by causing fluorescence in a number of different substances. He also found that X-rays can penetrate considerable thicknesses of materials of low atomic number, whereas substances of high atomic number are relatively opaque. Roentgen took the first steps in identifying the nature of X-rays by using a system of slits to show that (1) they travel in straight lines, and that (2) they are uncharged, because they are not deflected by electric or magnetic fields.‎Par. 3 The discovery of X-rays aroused the interest of all physicists, and many joined in the investigation of their properties. In 1899 Haga and Wind performed a single slit diffraction experiment with X-rays which showed that (3) X-rays are a wave motion phenomenon, and, from the size of the diffraction pattern, their wavelength could be estimated to be 10-8 cm. In 1906 Barkla proved that (4) the waves are transverse by showing that they can be polarized by scattering from many materials.‎Par. 4 There is, of course, no longer anything unknown about the nature of X-rays. They are electromagnetic radiation of exactly the same nature as visible light, except that their wavelength is several orders of magnitude shorter. This conclusion follows from comparing properties 1 through 4 with the similar properties of visible light, but it was actually postulated by Thomson several years before all these properties were known. Thomson argued that X-rays are electromagnetic radiation because such radiation would be expected to be emitted from the point at which the electrons strike the wall of a cathode ray tube. At this point, the electrons suffer very violent accelerations in coming to a stop and, according to classical electromagnetic theory, all accelerated charged particles emit electromagnetic radiations. We shall see later that this explanation of the production of X-rays is at least partially correct.‎Par. 5 In common with other electromagnetic radiations, X-rays exhibit particle-like aspects as well as wave-like aspects. The reader will recall that the Compton effect, which is one of the most convincing demonstrations of the existence of quanta, was originally observed with electromagnetic radiation in the X-ray region of wavelengths.‎‍‎‍When were X-rays discovered?‎
选项：
A: Par. 1
B: Par. 2
C: Par. 3
D: Par. 4
E: Par. 5
答案: 【 Par. 2】点我阅读全文

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第1周指针与字符串

小测验1.1

1、单选题：
​对于：‍int a[] = {5, 15, 34, 54, 14, 2, 52, 72};
int *p = &a[5];​则：‍​p[-2]的值是？‍​‍
选项：
A: 编译出错，因为数组下标越界了
B: 运行出错，因为数组下标越界了
C: 54
D: 2
答案: 【 54】点我阅读全文

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1制图规格及基本技能

1制图规格及基本技能——单元测试

1、单选题：
‎在土木工程制图中，断开界线可采用（   ）‎
选项：
A: 波浪线
B: 细实线
C: 细虚线
D: 粗单点长画线
答案: 【 波浪线】点我阅读全文

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项目10QT程序设计

项目10测试

1、单选题：
‌下面那个不是嵌入gui的特点（）。‍
选项：
A: 体积小
B: 运行时耗用资源少
C: 高度可移植
D: 代码简单
答案: 【 代码简单】点我阅读全文

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第一章 绪论

绪论测试题

1、单选题：
‏中国的万里长城属于（    ）。‍
选项：
A: 砖石结构
B: 钢结构
C: 钢筋混凝土结构
D: 木结构
答案: 【 砖石结构】点我阅读全文

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第一章风险管理与保险

第一章单元测试

1、单选题：
‎由于电线老化未及时维修，以至发生断路进而引起火灾，造成人员伤亡。导致该起人员伤亡的风险事故是‎
选项：
A: 电线老化
B: 火灾
C: 电线老化未及时维修
D: 电线断路
答案: 【 火灾】点我阅读全文

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项目1家用电器乒乓式电源开关控制系统设计

醒目1第5单元测试作业

1、单选题：
‌单片机的IO管脚一般为什么不能直接驱动继电器（ ）‏
选项：
A: 单片机的IO口输出的电流能力不能直接使继电器的线圈产生有效吸合力
B: 单片机的IO口不可以直接驱动
C: 因为单片机的IO管脚寄存器功能不全
D: 继电器的电压太大
答案: 【 单片机的IO口输出的电流能力不能直接使继电器的线圈产生有效吸合力】点我阅读全文

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