$A$ range of loudness of sound of $70-90$ decibels is rated as:

Is it true that carpets and curtains/drapes placed on the floor or wall surfaces can reduce noise level? Explain briefly.

The expanded form of $BOD$ is:

Why does fish mortality occur due to eutrophication?

Exposure to a noise level of $............$ or more for a short period can damage the eardrums,leading to permanent hearing impairment. (in $,dB$)

$DDT$ residues are rapidly passed through the food chain causing biomagnification because $DDT$ is: