Where are gates most commonly used? In studio recording environment

In the live mixing environment

In post-production

In the mastering process

Answer the question in the image! i just need 4s answer but is 3 is wrong correct me uwu

Suppose that you are in a room with 3 doors and a crack in the ceiling for light. that is all. the doors each have a sign on them that says what there is behind them. door #1. a pool of corrosive acid. door #2. a crocodile that hasn't eaten in 8 months. door #3. a solar "oven". a giant lens that focuses all the sunlight at the entrance of the door. you must choose a door, which door do you choose?

Sound waves can travel only in the aira. trueb.false