逻辑功能为输入有“0”时,输出就为“1”的门电路是()
A、与门
B、或门
C、与非门
D、或非门
参考答案:C
He is the last _____ his work. [ ]
A. finish
B. finishing
C. finishes
D. to finish
36伏作为安全电压是有条件的,是有时间限制的,是(),而不是绝对安全