App Logo

No.1 PSC Learning App

1M+ Downloads
The amount of residual chlorine left in public water supply for safety against pathogenic bacteria is about:

A0.05 to 0.5 ppm

B0.5 to 1.0 ppm

C1.0 to 5.0 ppm

D0.01 to 0.05 ppm

Answer:

A. 0.05 to 0.5 ppm


Related Questions:

The bond in which a header course is introduced after several stretcher courses is:
A rectangular beam 20 cm wide is subjected to a maximum shearing force of 10000 kg,the corresponding maximum shear stress being 30 kg/cm². The depth of the beam is
The liquid limit of a soil indicates its
The primary source of all water supply is
The instrument used to reproduce plans to a different scale is called