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單項(xiàng)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

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單項(xiàng)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

單項(xiàng)選擇題

When the garbage is mixed with some discharges having different disposal or discharge requirements, shall apply（）

A.any requirement appointed by the Officer
B.the most suitable requirement
C.the most stringent requirement
D.no requirement

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