'Heat islands' are produced due to

Which of the following is a major source of water and soil pollution?

Electrostatic Precipitator $(ESP)$:
$I.$ Is an electrical device to remove particulate matter present in the exhaust of thermal power plant.
$II.$ More than $99\, \%$ particulate matter can be removed by this method.
$III.$ $ESP$ has electrode wires and a stage of collecting plates.
Which of the statements given above are correct?

Photochemical smog always contains

Decibel $(dB)$ is a standard abbreviation used for the quantitative expression of

Which of the following is normally not an atmospheric pollutant?