题目内容

一根长度为L,截面积为S的长直导线,当长度增加一倍,截面积减小一半时,其电阻值为原来电阻值的多少倍? ( )

A. 2
B. 3
C. 4
D. 4.5

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Interest, as well as prospects, _____________ (be)important when one looks for a job.

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A. 对
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