利用键盘的方向键移动AP div元素时,一次按键只能移动()px。 ["1","2","3","4"]
在定影液中能抑制硫代硫酸钠被分解析出硫的化学药品是()。 ["CH3COOH","H3BO3","Na22SO4","Na22SO3"]
ZK3-A型电空转辙机油雾器油杯中的油量应不少于油杯容积的()1/3。 ["1/3","2/3","1/2","1/4"]
ZK3-A型电空转辙机的表示杆与活塞动程差不大于()mm。 ["1","0.5","2","1.5"]
柴油机吊缸时,对气缸盖应做哪些检查?
隔板导叶表面发生凹坑、凸包及出汽边弯曲时,怎么处理?