A.φ60H7/r6 B.φ60H8/k7 C.φ60h7/D8 D.φ60H9/f9 E.φ60H8/f7
A.2m B.1m C.5m D.10m
A.流量 B.揚(yáng)程 C.損壞程度 D.效率