An echo is heard after 0.8s, when a boy fires a cracker, 132m away from a tall building. Calculate the speed of sound?

Explanation

Echo time `(t) = 0.8 s`
Total distance travelled by sound wave
`2d=2xx132 m = 264 m`
From, speed of sound `V=2d//t`
`V=264 m//0.8s=330 m//s`