14 A and B are two hills at a distance 480 m apart A person

Last updated: 6/8/2023

14 A and B are two hills at a distance 480 m apart A person standing between the hills claps his hands and hears two echoes at the end of 1 second and 2 seconds The velocity of sound in air in m s is 1 320 m s 2 160 m s 3 330 m s 4 340 m s