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阅读大概理解文章意思,不必一句一词翻译出来、 The History of Electricity As early as the latter part of 16th century, experimenters were exploring the behavior of static electricity. Willian Gilbert experimented with electric charges and discharges. In 1750, Benjamin Franklin proved that lightning was electrical in nature. Neither investigator, discovered anything that was significant from the standpoint of electricity. Discovery of the presence of magnetism in certain rocks preceded the earliest knowledge of electricity. Such knowledge was common about 600 B. C. Applications of electrical knowledge were completely absent in this era. In 1800 Alessandro Volta discovered the principle of the electric battery. The voltaic cell was one of the most important discoveries in the history of the electrical art, because it provided a continuous source of appreciable amounts of electric power at reasonable low voltage. It was an essential component of the early communication systems, such as the telephone and telegraph. The first United States’ patent on the electrical telegraph was obtained by Jonhn Groat in 1800. The invention of a practical electromagnet was announced by Joseph Henry in 1827. These inventions by Groat and Henry opened the way for a still more significant invention, the electromagnetic telegraph. The principle of this forerunner of the communications industry was conceived in 1830, proven practical in 1837, and patented in 1840 by Samuel Finley Bressse. Morse. Few developments have had greater impact on American life than Morse’s invention. His idea paved the way for the first system of electrical communication, this in turn led to the telephone and later to the wireless telegraph. The discovery of electromagnetic induction by Michael Faraday in 1831 established many principles for modern machines. One of the first important developments based on the disclosures of Faraday was the DC generator. Motors generators, transformers and many other electrical devices found in heavy electrical industry were made possible by the discoveries of Faraday. The contributions of Faraday in the electrical power industry and comparable to those of Morse in the field of communications. With the development of the high-resistance carbon filament lamp by Thomas Edison in 1880, the DC generator became one of the essential components of the constant-potential lighting system. Commercial lighting and residential lighting became practical and the electric light and power industry were born. One of the most common uses for direct current during this period was for street lighting. The first transformer was announced in 1883. This device probably did more to revolutionize that the high-voltage low-current systems over the low-voltage high–current systems of power transmission were well-known. Following the discovery of the transformed to higher voltages for transmission over great distances (several hundred miles), and then reduce by transformers to lower values for utilization. In 1888 Nikola Tesla was granted a patent on the polyphase AC induction motor, which soon became the most commonly used motor for supplying large amounts of power in its improved state. It is most extensively used today . In 1876 Alexader Graham Bell invented the telephone. This device was soon put into use and, as a result, another huge industry was established. New Words static ['stætɪk] adj. 静电的;静止的;静态的 standpoint ['stæn(d)pɒɪnt] n. 立足点 magnetism ['mægnɪtɪz(ə)m] n. 磁场,磁力 voltaic [vɒl'teɪɪk] adj. 付打的 patent ['pæt(ə)nt; 'peɪt(ə)nt] n. 专利 electromagnetic [ɪ,lektrə(ʊ)mæg'netɪk] n. 电磁铁;电磁体 filament ['fɪləm(ə)nt] n. 灯丝 polyphase ['pɒlɪfeɪz] adj. 多相的
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举一反三
【单选题】间接费用指的是()。
A.
管理费用
B.
销售费用
C.
直接计入该种产品成本的材料费用
D.
在各种产品之间进行分配的费用
【判断题】生产费用按其计入产品成本的方式不同,可以分为直接费用和间接费用。直接费用包括直接材料和直接人工,间接费用是指制造费用。( )
A.
正确
B.
错误
【单选题】继承人有下列( )行为之一的,不会丧失继承权。
A.
故意杀害被继承人的;
B.
为争夺遗产而杀害其他继承人的;
C.
与被继承人分开居住的;
D.
伪造、篡改或者销毁遗嘱,情节严重的;
【单选题】间接费用指的是( )
A.
管理费用
B.
直接计入该种产品成本的材料费用
C.
在各种产品之间进行分配的费用
D.
销售费用
【简答题】简述三圈环流的形成。
【单选题】对汇率制度是朝着浮动方向发展的这一论述的原因说法不正确的是( )。
A.
越来越多的人认识到,浮动汇率制度市场性强、微调频繁,从而能较好地缓和外部因素对本国经济的冲击
B.
现代经济学证明,政府对经济信号的敏感程度远不如自由市场的参与者,政府对经济资源的配置也远不如在市场价格引导下对资源配置的效率高
C.
提高风险意识,建立必要的风险监测和防范机制以外,一国规避国际经济、金融风险的根本立足点还在于努力发展和完善本国的经济、金融体制,增强本国经济、金融实力,从而切实增强抵御国际金融市场投机势力冲击的能力
D.
对发展中国家来说,特别是那些开放程度高、外汇管制已经减弱、国内金融市场发育已经比较充分的发展中国家来说,选择弹性较弱的汇率制度并在适当的时候改行浮动汇率制度应该是较为明智的
【单选题】( )是指项目投入物所产生的经济费用。
A.
直接效益
B.
间接效益
C.
直接费用
D.
间接费用
【单选题】甲经营家族企业多年,身价颇高,没有其他亲人,只有两个儿子乙和丙。偶然间,甲发现自己身患癌症,已至晚期。甲一直重视帮其打理生意的大儿子乙,就立遗嘱,将四分之三的财产留给儿子乙,其余财产留个儿子丙。丙知晓后非常不满,为争夺遗产雇人痛殴乙致残,以示警告。乙认为应尽快继承企业,以免夜长梦多,就找机会将重病的甲遗弃到国外。后乙追悔莫及,将甲接回,甲临终前对乙和丙的行为表示原谅。下列表述正确的是( )
A.
丙丧失了继承权
B.
乙丧失了继承权
C.
甲宽恕乙和丙之后,乙和丙可以向法院申请恢复继承权
D.
乙的继承权自动恢复
【单选题】人机工程学主要研究的内容是( )。
A.
人与机器的关系
B.
机器如何适应人
C.
环境、能源和人的关系
D.
人、机、环境系统三大要素
【单选题】以下关于国际公认的偿债能力标准的认识错误的是( )。
A.
全部外债占GDP的比重不超过20%
B.
偿债率(中长期外债还本付息额相当于经常账户外汇收入的比重)不超过25%
C.
外汇储备与短期外债余额相比不超过100%
D.
债务率(外债余额相当于经常账户外汇收人的比重)不超过200%
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