某电路处在短路状态时，外电路电阻震为零，故短路电流在R上压降U（）。
A.等于0
B.不等于0
C.等于电源电势
D.不能确定
参考答案：A
下列宜切薄片的是
A．杜仲B．黄芪C．甘草D．槟榔E．何首乌
Don't hurry. We still have _____ time. [ ]
A. little
B. a little
C. few
D. a few
