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單項選擇題

Bacteria which live are said to be aerobic（）

A.in the presence of oxygen
B.without oxygen
C.in the presence of nutrition
D.without nutrition

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單項選擇題

It is that reduce the BOD by converting the organic content of the sewage to a chemically and organically inert sludge（）

A.the bacteria
B.oxygen
C.oxidizing function
D.agitation function

單項選擇題

The basic process of biological sewage treatment consists of the liquor either by bubbling air through it or by agitating the surface（）

A.oxygenating
B.oxidizing
C.deoxygenating
D.proportioning

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