塑料间隙规用于测量（） ["活塞直径","主轴瓦间隙","连杆孔失圆","活塞环开口间隙"]
依据华电集团《反违章管理指导意见》，指挥性违章的定义是什么？
All of the following are recognized distress signals under the Navigation Rules EXCEPT（）. ["a green star signal","orange-colored smoke","red flares","the repeated raising and lowering of outstretched arm"]
华电集团《反违章管理指导意见》，习惯性违章是如何定义的？
All of the following are distress signals under the Rules EXCEPT（）. ["International Code Signal "AA"","orange-colored smoke","red flares","the repeated raising and lowering of outstretched arm"]
什么叫电力系统的中性点？
