单项选择题
The main purpose of port State control is not to（）
A.prevent an unsafe ship proceeding to sea B.prevent a ship threatening the marine environment C.fine the ships D.confirm a safe sailing
单项选择题 If two A.C.generators are to be operated in parallel, the load is distributed evenly by（）
单项选择题 The treatment of the fuel oils involves storage, heating, filtering and（）
单项选择题 Which of the following items don’t belong to dock repair works?（）
