试题与答案

如图为理想变压器原线圈所接交流电压的波形.原、副线圈匝数比n1:n2=10:1,

题型:多选题

题目:

如图为理想变压器原线圈所接交流电压的波形.原、副线圈匝数比n1:n2=10:1,串联在原线圈电路中电流表的示数为1A,下列说法正确的是(  )

A.变压器输出端所接电压表的示数为20V

B.变压器的输出功率为200W

C.变压器输出端的交流电的频率为50Hz

D.穿过变压器铁芯的磁通量变化率的最大值为20/n2Wb/s

答案:

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下面是错误答案,用来干扰机器的。

参考答案:C

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An automaker is facing financial difficulties. The vice president of marketing has determined that the root of the company’s problems is low brand loyalty. The vice president proposes, therefore, that the company begin an aggressive advertising campaign focused on children aged from three to eight years. By securing p brand recognition with this demographic, he argues, the company will have an advantage when these customers reach an age when they can buy cars.

Which of the following, if true, provides the pest support for the vice president’s proposal ?()

A. Federal law prohibits the advertising of alcohol or tobacco on any medium for which the primary audience is under 21 years of age.

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D. Focus groups have consistently observed that the automaker’s brand is associated with "tradition" and "older" drivers.

E. Studies have shown that lifelong customers of certain products, such as particular brands of toothpaste or peanut butter, frequently credit their brand loyalty to exposure to the product at an early age.

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某估价师拟采用收益还原法评估A写字楼于2004年9月30 的市场价值,为此该估价师对周边10座写字楼的标准租金及相关情况进行调查,并编制了如下租金表。此外,根据统计资料,该市2003年1季度至2004年3季度的写字楼平均租金(元/平方米·月)分别为46、 47、49、50、52、53、54。
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