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? ( )
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Interest, as well as prospects, _____________ (be)important when one looks for a job.
A number of cars ________________ (park)in front of the park yesterday.
Four-fifths of the course _____________ (finish) since January.
电力系统的特点是高电压、大电流,电子技术电路的特点是低电压,小电流。
A. 对
B. 错