单项选择题
The treatment of the fuel oils involves storage, heating, filtering and（）
A.centrifuging B.pressurizing C.atomization D.igniting
单项选择题 Which of the following items don’t belong to dock repair works?（）
单项选择题 During the diesel engine running, the water level of F.W expansion tank should normally kept in the （） level of glass tube.
单项选择题 （） is not installed on the main switchboar.
