A.15mA B.30mA C.45mA D.75mA
A.1m B.1.2m C.1.5m D.1.8m
A.3~4m B.5~6m C.8~10m
A.1B.2C.3D.4
A.用吊袋和吊绳传送 B.上下抛掷传送物品和工具 C.地面人员登高将工具送上去 D.用吊袋传送或上下抛掷都可以