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问题 多项选择题

下列属于连续调查的是（）。

A.工厂的产品生产

B.原材料的投入

C.能源的消耗

D.人口的出生

E.人口的死亡

答案

参考答案：A, B, C, D, E

解析：连续调查是为了观察总体现象在一定时期内（通常是一年内）的数量变化，它要求随着调查对象的发展变化，连续地进行调查登记。连续调查的资料是说明现象的发展过程，目的是为了解社会现象在一段时期的总量。题中五项需要在调查期内连续登记，然后再进行加总，因此都属于连续调查。

选择题
如图所示，处在磁感应强度为B的匀强磁场中的单匝矩线圈abcd，以恒定的角速度ω绕ab边转动，磁场方向垂直于纸面向里，线圈所围面积为S，线圈导线的总电阻为R．t=0时刻线圈平面与纸面重合，且cd边正在离开纸面向外运动．则正确的是（　　）

A．时刻t线圈中电流的瞬时值icosωt

B．线圈中电流的有效值I

C．线圈中电流的有效值I=

D．线圈消耗的电功率P

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单项选择题

The "standard of living" of any country means the average person’s share of the goods and services which the country produces. A country’s standard of living, (1) , depends first and (2) on its capacity to produce wealth." Wealth" in this sense is not money, for we do not live on money (3) on things that money can buy. "Goods" such as food and clothing, and "services" such as transport and " (4) ". A country’s capacity to produce wealth depends upon many factors, most of (5) have an effect on one another. Wealth depends (6) a great extent upon a country’s natural resources. Some regions of the world are well supplied with coal and minerals, and have a fertile soil and a (7) climate; other regions possess none of them.

Next to natural resources (8) the ability to turn them to use. China is perhaps as well (9) as the USA in natural resources, but suffered for many years from civil and (10) wars, and (11) this and other reasons was (12) to develop her resources. (13) and stable political conditions, and (14) from foreign invasion, enable a country to develop its natural resources peacefully and steadily, and to produce more wealth than another country equally well (15) by nature but less well ordered.

A country’s standard of living does not only depend upon the wealth that is produced and consumed (16) its own borders, but also upon what is indirectly produced through international trade. (17) , Britain’s wealth in foodstuffs and other agricultural products would be much less if she had to depend only on (18) grown at home. Trade makes it possible for her surplus manufactured goods to be traded abroad for the agricultural products that would (19) be lacking. A country’s wealth is, therefore, much influenced by its manufacturing capacity, (20) that other countries can be found ready to accept its manufactures.

14（）

A.liberty

B.freedom

C.prevention

D.liberation
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