单项选择题
A number of biological sewage treatments plants are in ...
单项选择题A number of biological sewage treatments plants are in use at sea but nearly all work on the principle called （）
A.deoxygenating B.extended aeration C.oxygenating D.bubbling air
Which of the following would not be burnt in an inciner...
单项选择题Which of the following would not be burnt in an incinerator on board?（）
A.waste oil B.waste cloths C.Oil rags D.Waste food
During waste clothes being charged into an incinerator,...
单项选择题During waste clothes being charged into an incinerator, the auxiliary burner（）.
A.should be stopped manually B.keeps the combustion as usual C.would be cut off by an interlock D.would replace the waste oil burner and keep going on
