正常情况下同心针电极记录到的MUAP波宽是()
A.3~16ms
B.3~16μs
C.10~15ms
D.3~10ms
E.7~12ms
参考答案:A
Alice is a hard-working student. But _______, she didn't pass the Chinese exam. [ ]
A. in fact
B. to our surprise
C. by the way
D. as a result
低压供电线路,其负荷电流为20A及以下时,宜采用();其负荷电流为50A以上时,宜采用经电流互感器接入式的电能表。