遥信信号可分为()信号进行调试。
A、变位;
B、掉牌;
C、事故及告警;
D、音响。
参考答案:A, B, C
Steve isn’t as ______ as Kelly. He often makes mistakes in his writing.
A.careless
B.tidy
C.careful
D.difficult
户外20kV高压配电装置场所的行车通道上,应设置行车安全限高标志的安全距离为0.9米。