在线电压为220v的工频三项电网中,两相触电时,人体承受的电压()。
A.为220V
B.为380V
C.为110kv
D.与距离有关
参考答案:B
It was on July 1, 2006 ___ Qinghai-Tibet railway began operation, ____ is a symbolic project in
China's West Development Strategy.[ ]
A. when; that
B. that; when
C. which; when
D. that; which
“商品”与“顾客”两个实体集之间的联系一般是______。
A.一对一
B.一对多
C.多对一
D.多对多