Which of the following is not a pollutant?

Find the incorrect statement with respect to a catalytic converter.

The soil pollutants that affect the food chain and food web by killing microorganisms and plants are:

Consider the following statements:
$I.$ Algal blooms are formed by free-floating algae.
$II.$ Algal blooms cause fish mortality and deterioration of water quality.
$III.$ Water hyacinth, the world's most problematic aquatic weed, is also called 'Terror of Bengal'.
Which of the statements given above are correct about algal blooms?

The process of aging of a lake by human activities occurs at a very rapid rate,which is called......

Currently,the Government of India has approved the blending of alcohol in petrol. What percentage of alcohol blending in petrol has been approved?