NEET Questions Solved


Microorganisms are used during which stage of the purification of the sewage water?

(1) Primary treatment

(2) Secondary treatment

(3) Tertiary treatment

(4) Both (1) and (2)

(2) The aerobes are used to consume the organic matter during the secondary stage follwed by anaerobic digestion of the aerobes themselves.

Difficulty Level:

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