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【单选题】
某220kV变电所,总占地面积为12000m2(其中接地网的面积为10000m2),220kV系统为有效接地系统,土壤电阻率为100Ω?m,接地短路电流为10kA,接地故障电流持续时间为2s,工程中采用钢接地线作为接地网及电气设备的接地(钢材的热稳定系数取70)。试根据上述条件计算下列各题。站内单相接地入地电流为4kA,最大跨步电位差系数取0.24,接地电阻0.35Ω,则最大跨步电位差为()。
A.
336V
B.
480V
C.
960V
D.
1400V
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举一反三
【单选题】Don't get this kind of ink on your shirt, for it _____ wash out. [     ]
A.
can't
B.
mustn't
C.
shouldn't
D.
won't
【简答题】A.succeed B.realize C.gain D.overcome
【判断题】视准线布设时应考虑大气折光的影响。 ( )
A.
正确
B.
错误
【简答题】A.create B.receive C.feel D.overcome
【简答题】How to Overcome Cultural Barriers in Internet Business ?
【简答题】Australians are advised to overcome the old taboo of ______.
【简答题】A.catch B.suffer C.diverse D.overcome
【判断题】Li Ming is learning ink and wash painting at the Department of Art.
A.
正确
B.
错误
【简答题】A.dispose B.transfer C.abandon D.overcome
【单选题】Take care! Don’t drop ink on your shirt, for it _______ easily.
A.
won’t wash out
B.
won’t be washed out
C.
isn’t washed out
D.
isn’t washing out