Q.3 The material generally used for soundproofing of rooms like a recording studio and auditorium etc., is

1. cotton

2. )coir

3. wood

4. styrofoam

Q.13 The major source of noise pollution, worldwide is due to

1. office equipment

2. transport system

3.sugar, textile, and paper industries

4. oil refineries and thermal power plants

Match correctly the following and choose the correct option :

The correct matches are