mooc答案类别

第一讲绪论

第1讲绪论

1、单选题：
各向同性假设认为，材料沿各个方向具有相同的               。‎  ‎​‎
选项：
A: 力学性质；
B: 外力；  
C: 变形；  
D: 位移。
答案: 【 力学性质；】点我阅读全文

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第一周信息技术与中学地理教学融合概说

第一周单元测验

1、单选题：
‎我国在（  ）年明确界定了信息技术与教育“深度融合”的新概念。‍‎‍
选项：
A:  2011
B: 2012
C: 2013
D: 2014
答案: 【 2012】点我阅读全文

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一、公务员热与公务员制度

第一单元测试题

1、单选题：
‌世界上最早确立公务员制度的国家是‎
选项：
A: 美国
B: 英国
C: 法国
D: 德国
答案: 【 英国】点我阅读全文

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第一章 互联网金融概述

第一章 单元测验

1、单选题：
‎关于互联网金融的发展，以下哪一个说法是错误的（）‌
选项：
A: 1995年互联网起步开始
B: 2003年电子商务元年
C: 2007年第三方支付元年
D: 2013年互联网金融元年
答案: 【 2007年第三方支付元年】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：
下列食品不是按照加工工艺分的是__   __。‎‎
选项：
A: 罐头制品；
B: 烟熏制品；
C: 发酵制品；
D: 饮料制品；
答案: 【 饮料制品；】点我阅读全文

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第一章自然科学与法学--环境法的自然科学基础

第一章单元测试

1、单选题：
‎下列哪一项不是环境法保护的对象(      )​
选项：
A: 南极
B: 城市环境
C: 湿地
D: 宠物狗
答案: 【 宠物狗】点我阅读全文

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模块一电路的基本概念与基本定律

基尔霍夫定理及其应用随堂测验

1、单选题：
‌对于基尔霍夫定律，以下描述正确的是（       ）。‌
选项：
A: 基尔霍夫电流定律反映了回路中电流相互制约的关系
B: 基尔霍夫电流定律反映了节点上电流相互制约的关系
C: 基尔霍夫电压定律反映了回路中电流相互制约的关系
D: 基尔霍夫电压定律反映了节点上电流相互制约的关系
答案: 【 基尔霍夫电流定律反映了节点上电流相互制约的关系】点我阅读全文

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学习情境一 跨境店铺注册操作

eBay平台注册流程

1、单选题：
‍注册eBay平台时中国大陆账户使用（  ）进行用户验证。‎
选项：
A: 信用卡
B: 双币信用卡
C: 邮箱
D: 电话
答案: 【 双币信用卡】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03章生产费用要素的归集与分配

第03章单元测验

1、单选题：
‎“在途物资”账户的期末借方余额表示(    )。​
选项：
A: 库存物资的实际成本  
B: 库存物资的计划成本
C: 在途物资的实际成本
D: 在途物资的计划成本
答案: 【 在途物资的实际成本】点我阅读全文

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