[单项选择]The night is not what it was. Once, the earth was cast half in shadow. Then came fire, candle, and light bulb, gradually drawing back the curtain of darkness. But a brighter world has its drawbacks. An estimated 30 percent of outdoor lighting—plus even some indoor lighting—is wasted. Inefficient lighting costs U.S. about $10.4 billion a year, according to bob Gent of the International Dark Sky Association, a nonprofit that aims to control light pollution.
Last year, in Sydney, an estimated 2.2 million Australians switched off their lights during "Earth Hour", briefly reducing that city’s energy use by more than 10 percent. Motivated by such trends, more than two dozen cities worldwide went dim on March 29 this year in an hour-long demonstration.
A number of groups are trying to measure light pollution and assess its effect on the environment in the hope that people will reduce their own contribution to the problem. Scientists are trying to report how many stars we can
A. strongly opposes outdoor light services
B. has lost some money in energy trade
C. has profited from the lighting business
D. makes efforts to reduce light pollution

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[简答题]水锤现象有何危害？

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[判断题]工艺系统的重力、惯性力、传动力会使工件在加工时发生变形和位移，影响加工精度。( )

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[单项选择]头痛伴癫痫见于（）
A. 偏头痛
B. 青光眼
C. 三叉神经痛
D. 神经功能性头痛
E. 脑内寄生虫病

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[单项选择]下列( )是国民经济评价中必选的分析指标。
A. 投资收益率
B. 内部收益率
C. 基准收益率
D. 净现值

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[多项选择]下列有关契税的说法中正确的是（）。
A. 纳税人是境内转移土地、房屋权属承受的单位和个人
B. 纳税人是使用城市、县城、建制镇和工矿区土地的单位和个人
C. 国有土地使用权出让、土地使用权出售、房屋买卖时，以成交价格为计税依据
D. 计税依据是不动产的价格
E. 计算公式为：应纳税额=计税依据×税率

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[判断题]《行规》规定,在到发线装卸货物(不含行包)时, 须经车站调度员准许,并由车站调度员将道岔锁闭在不能通往该线路的位置。作业完
毕后应及时报告车站调度员。
A.正确
B.错误

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[填空题]《中国银监会关于支持商业银行进一步改进小型微型企业金融服务的补充通知》，文号（）。

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[单选题](238074)曲轴安装硅油减振器的目的是为了防止发生( )共振。(1.0分)
A.往复
B.扭转
C.径向
D.轴向

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[简答题]组织结构的类型有哪几种？

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[单项选择]“整个市区印证了11世纪至13世纪的欧洲巨大变迁”指的普罗万小镇位于哪个国家？（）
A. 法国
B. 意大利
C. 德国

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[单选题]按照埋弧焊焊剂化学性质来分类的焊剂种类为()。
A.A、氧化性焊剂
B.B、惰性焊剂陶质焊剂
C.C、惰性焊剂