Maximum permissible residual chlorine in treated water should be __________ mg/litre.

Question: Maximum permissible residual chlorine in treated water should be __________ mg/litre.
[A].

0.001 to 0.01

[B].

02 to 0.3

[C].

2 to 3

[D].

5 to 10

Answer: Option B

Explanation:

No answer description available for this question.