单项选择题
（） are used for cargo handling.
A.Cranes B.Mooring winches C.Windlasses D.Foreman
单项选择题 In a hydraulic system, （） are used to protect the system from over pressure.
单项选择题 A hydraulic motor may be driven by （）.
单项选择题 A high rate of separation between oil and water is favored by （）.
