单项选择题
A.blocks B.hooks C.cargo sling D.derricks
Before opening the hatch covers, all cleats are to be （...
单项选择题Before opening the hatch covers, all cleats are to be （）.
A. released B. secured C. taken away D. sent out
A （）is used for lifting long heavy cargo.A.derrickB.cra...
单项选择题A （）is used for lifting long heavy cargo.
A.derrick B.crane C.jumbo boom D.boom
（）cargo is unloaded by huge grabs on cranes or by large...
单项选择题（）cargo is unloaded by huge grabs on cranes or by large grain elevators.
A. Dry B. Dry general C. Dry bulk D. Liquid
