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Chapter Eight Gender Difference in Communication 交际中的性别差异

Quiz随堂测试

1、判断题：
Gender difference in intercultural communication doesn’t include nonverbal communication.​
选项：
A: 正确
B: 错误
答案: 【 错误】点我阅读全文

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第0章 绪论

第0章 单元测验

1、单选题：
‎本课程是属于什么性质的课程?‌
选项：
A: 技术基础课
B: 基础课
C: 专业课
D: 核心课
答案: 【 技术基础课】点我阅读全文

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第一讲感知移动设备

第一讲单元测验

1、单选题：
‌领袖和跟风者的区别在于‏
选项：
A: 创意
B: 创业
C: 创新
D: 创造
答案: 【 创新】点我阅读全文

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第一讲中国法治建设的历程与启示上

第一讲中国法治建设的历程与启示上

1、单选题：
‎新中国成立前夕颁布的具有临时宪法作用的是？‎
选项：
A: 《中华人民共和国宪法》
B: 《中华人民共和国土地改革法》
C: 《中国人民政治协商会议共同纲领》
D: 《中国人民政治协商会议组织法》
答案: 【 《中国人民政治协商会议共同纲领》】点我阅读全文

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Unit1WritingaSummary

Unit1WritingaSummary

1、单选题：
‎Besides key points, the other element a summary should include is:​​
选项：
A: words and phrases from the original text
B: your own comments
C: the thesis statement
D: the author’s name
答案: 【 the thesis statement】点我阅读全文

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任务一 电机连续运转PLC控制与实现

单元测试二

1、单选题：
​PLC输入点得电。对应程序中的常开触点怎么变化？​​​
选项：
A: 不变化
B: 由常开变为常闭
C: 由常闭变常开
D: 以上都有可能
答案: 【 由常开变为常闭】点我阅读全文

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01经济法初探

单元测验

1、单选题：
‎下列哪一项不是经济法的调整对象？​
选项：
A: 经济管理关系
B: 工商局长与其下属的领导与被领导关系
C: 经济协调关系
D: 组织内部经济关系
答案: 【 工商局长与其下属的领导与被领导关系】点我阅读全文

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第1周——初识C语言从认识变量和常量开始

codeblocks介绍——从Hello World开始

1、单选题：
‌#include <stdio.h>是‎
选项：
A: 编译预处理指令
B: 语句
C: 函数
D: 程序入口
答案: 【 编译预处理指令】点我阅读全文

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1绪论

1绪论

1、单选题：
‍ 公共事业的特征是什么‍‍‍
选项：
A:  公共性、公益性、非物质性、非营利性
B: 公共性、劳务性、非物质性、非营利性
C: 公共性、公益性、发展性、非营利性
D: 公共性、阶级性、劳务性、非营利性
答案: 【  公共性、公益性、非物质性、非营利性】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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