IS 2296-1982 के अनुसार, जल को पाँच श्रेणियों (A से E) में वर्गीकृत किया गया है। श्रेणी E किसे निरूपित करती है?

Turbidity in water is measured on which standard scale?

Mudball formation in rapid sand filters is the result of:

In a water sample, if 2 mg of platinum cobalt salt is dissolved in 1 litre of distilled water, then the colour produced is equal to: