A.發(fā)電、配電、輸電、變電、用電 B.發(fā)電、變電、輸電、變電、配電、用電 C.發(fā)電、變電、配電、輸電、用電 D.發(fā)電、輸電、變電、配電、用電
A.220V B.250V C.380V D.500V
A.直流電流 B.交流電流 C.直流電壓 D.交流電壓