A. Foaming
B. Odour nuisances
C. Undesirable plant growth
D. Turbidity
A. Sedimentation tank
B. Circular clarifier
C. Mechanical flocculation
D. Chemical coagulation
A. Allows visible solar radiation (ultraviolet) of short wave-length to pass through
B. Reflects and absorbs the longer wavelength (infra-red) radiations
C. Prevents solar heat being radiated out completely, resulting in ‘heat trap’ i.e., global warming
D. All A., B. and C.
A. Files
B. Algae
C. Micro-organisms
D. Mosquitoes
A. Natural aeration of water stream
B. Photosynthetic action of algae
C. Both A. & B.
D. Neither A. nor B.
A. Hydrochloric acid
B. Lime
C. Copper sulphate
D. Sodium sulphate
A. Flood
B. Cyclone
C. Decrease in food productivity
D. All A., B. and C.