Environmental Engineering in CE
Disinfection of water is done to destroy pathogenic bacteria and thus prevent water-borne diseases. Disinfection of water may be done by the use of

Chlorine or its compounds
Ultraviolet light for irradiation of water
Ozone and iodine
All of these

ANSWER DOWNLOAD EXAMIANS APP

Environmental Engineering in CE
Aerobic biological oxidation ponds used for the purification of polluted water

Destroys/removes pathogen much more effectively if the sewage is chlorinated
Is not very effective for nonbiodegradable substances (e.g. ABS) containing effluents
All of these
Destroys/removes pathogen from the sewage

ANSWER DOWNLOAD EXAMIANS APP