电机车架空线与巷道或顶棚之间的距离不得小于()m
A、0.2
B、0.3
C、0.4
参考答案:A
A chain bridle is used when towing astern because it().
A.is easy to connect
B.provides an effective catenary and absorbs shock due to its weight
C.makes rigging a swivel unnecessary
D.prevents the tow from yawing by the drag of the chains in a seaway
南水北调西线调水设想源于中国哪位地质学家?()