Write any two differences between echo and reverberation. Why the speed of sound in hot air is more than that in the cold air​

1) Because of the size and time the sound wave moves, an echo is typically transparent and easy to discern. Since reverberations typically don't have enough distance or time to fly, they will pile up on top of each other, making it impossible to understand.

People will detect an echo if the distance between the source of the sound and the reflected body is greater than 50 feet. When a sound wave is bounced off a nearby surface, it may create a reverberation.

2) The speed of sound in hot air is more than that in cold air because air molecules are traveling faster in hot air.

Explanation:

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.