UZ-0.3/0.5型电缆,缆芯绞合节径比应不大于()。
A.5;
B.8;
C.10;
D.12。
参考答案:A
30.—Peter looked tired and a little absent-minded at the meeting.
—He _____ up too late.
A.may stay
B.could stay
C.should have stayed
D.must have stayed
从()到列车停下为止,列车所运行的距离叫制动距离。