Question

When is air said to b polluted ?

Answer 1

Air pollution occurs when harmful or excessive quantities of substances including gases, particles, and biological molecules are introduced into Earth's atmosphere.

Answer 2

$when \: air \: is \: contaminated \:$

$by \: harmful \: substances \: then$

$air \: is \: said \: to \: be \: polluted$

$mark \: as \: brainielist \: answer$