多项选择题
为了保证KJ从进路锁闭到进路解锁这段时间内保持吸起,KJ必须具有自闭电路。
判断题为了保证KJ从进路锁闭到进路解锁这段时间内保持吸起,KJ必须具有自闭电路。
A. B. C. D.
单项选择题
Small __________ electrons are, they play an important ...
单项选择题Small __________ electrons are, they play an important role in the formation of electric current. A、no matter how B、as C、while D、even though