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單項(xiàng)選擇題

The extended aeration process consists of （） the liquor either by bubbling air through it or by agitating the surface.

A.deoxygenating
B.oxygenating
C.chemicalizing
D.disinfecting

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單項(xiàng)選擇題

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

單項(xiàng)選擇題

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