单项选择题
The duty of a deck winch is to lift and lower a load by means of a fixed rope on （）.
A.a warp end B.a mooring winch C.a worm gear D.a barrel
单项选择题 Most anchor handling equipment incorporates （） for mooring purposes.
单项选择题 A variable displacement system of hydraulic drives consists of （）.
单项选择题 Which of the following hydraulic systems is not one of the three sub-division of the Hydraulic drive system?（）
