单项选择题
When the ship is going to enter into the harbor,（）
A.change from heavy fuel oil to diesel oil for mail engine B.pumping oil bilge water C.change sea chest form high level one to lower one D.test emergency generator
单项选择题 Which of the following represents the significance the fuel oil cetane number?（）
单项选择题 Which of the following conditions is realized by the turbo-charging of a previously naturally aspirated diesel engine?（）
单项选择题 Piston cooling fins are located（）
