Maximum permissible limit of industrial noise as recommended by World Health Organisation (WHO) is __________ decibels.
A. 35
B. 75
C. 95
D. 105
Answer: Option B
A. 35
B. 75
C. 95
D. 105
Answer: Option B
Fluorosis is caused due to the presence of excessive amount of __________ in drinking water.
A. Mercury
B. Lead
C. Fluoride
D. Arsenic
Smog is not formed due to the presence of __________ in the atmosphere.
A. SO2
B. NOx
C. CO2
D. Any of these
Dose of chlorine for disinfection of water is about __________ mg/litre of water.
A. 0.01
B. 0.1
C. 0.3
D. 1
explain
why