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第一讲认识博弈论

第一讲测试

1、单选题：
‍博弈论的基本要素以下内容，除了（  ）。‏
选项：
A: 局中人
B: 均衡
C: 策略与策略集
D: 支付与支付函数
答案: 【 均衡】点我阅读全文

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第1讲课程简介

Android基础

1、单选题：
‌Android底层是基于什么操作系统‌
选项：
A: Java
B: Mac OS
C: Windows
D: Linux
答案: 【 Linux】点我阅读全文

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第17章光的干涉

光的干涉单元测验

1、单选题：
‏真空中波长为λ的单色光，在折射率为n的均匀透明媒质中，从A点沿某一路径传播到B点，路径的长度为l．A、B两点光振动相位差记为Δφ. 则‍‏‍
选项：
A: l＝3 λ/ 2，Δφ＝3π．
B: l＝3λ/ (2n)，Δφ＝3 nπ
C: l＝3 λ / (2n)，Δφ＝3π．
D: l＝3nλ/ 2，Δφ＝3 nπ．
答案: 【 l＝3 λ / (2n)，Δφ＝3π．】点我阅读全文

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第一章 绪论

第一章单元测验

1、单选题：
‎广告学的学科特色​‎​
选项：
A: 强理论性和思辨性
B: 名副其实的强应用性
C: 应用性和理论性都很突出
D: 无
答案: 【 名副其实的强应用性】点我阅读全文

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第一讲 企业模拟运营——ERP沙盘基础讲解

厂房规则自测

1、单选题：
‎购买厂房时，价款在什么时候扣除？​
选项：
A: 购买时
B: 季初
C: 季末
D: 年末
答案: 【 购买时】点我阅读全文

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第1周 从一间书屋说起数据库背景与知识准备

我做好知识准备了吗？

1、单选题：
‏数据库系统投入使用后，负责管理和维护、确保数据库安全和系统运行正常的人员或团队是（）。‎
选项：
A: DBA
B: 系统分析员
C: 应用程序员
D: 终端用户
答案: 【 DBA】点我阅读全文

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第一章导论

第一章一带一路”的战略枢纽

1、单选题：
‎中国将依托以下哪三个省份的区位优势，打造21世纪海上丝绸之路与陆上丝绸之路经济带有机衔接的重要门户？‍
选项：
A: 云南、广西、贵州
B: 云南、广西、西藏
C: 云南、四川、西藏
D: 四川、广西、西藏
答案: 【 云南、广西、西藏】点我阅读全文

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第一章计划职能

单元测验

1、单选题：
SO策略是指：‏A.利用优势，把握机会   B.利用优势，克服威胁‏C.减少劣势，把握机会   D.减少劣势，克服威胁‏‎‏
选项：
A: A
B: B
C: C
D: D
答案: 【 A】点我阅读全文

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Lesson 2

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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第一讲半导体导论

01-02杂质半导体

1、单选题：
‏N型半导体中的多子是（）。‍
选项：
A: 电子
B:  空穴
C: 正离子
D:  负离子
答案: 【 电子】点我阅读全文

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