单项选择题 To receive oil residues from the purification of fuel and lubricating oils in the machinery spaces, what kind of tank(s) should be provided on board?（）

单项选择题 Which cause of following will not lead to refrigeration plant short-cycle?（）

单项选择题 On modern ships, centrifugal pump with a self-primer has replaced reciprocating pump as bilge pump because（）