装复断电器时要求触点保持同心,接触面积()。 ["A、不小于85%","B、不大于85%","C、不小于60%","D、不大于60%"]
电空制动控制器有哪几个工作位置?
单线有人看守道口口笛备品数量标准为()个。 ["A.1","B.2","C.3","D.4"]
肾蒂内自前向后排列的结构是() ["A、肾动脉、肾静脉、肾盂","B、肾动脉、肾盂、肾静脉","C、肾盂、肾静脉、肾动脉","D、肾静脉、肾动脉、肾盂","E、肾静脉、肾盂、肾动脉"]
发动机转速不稳,怠速时抖动,拔下某缸高压分线,转速无变化,用高压分线作跳火试验,有火,则应检查更换()。 ["A、火花塞","B、高压分线","C、分火头","D、分电器盖"]
电空阀的作用是什么?