a) The speed of sound was measured with a loudspeaker and a microphone spaced [[$ 20 $]] m apart. The sound took [[$ 60 $]] ms to travel through the interval. Based on the measurement, calculate the speed of sound.

The speed of sound is:


[[$ v ≈ $]] m/s

b) You will hear a thunder [[$ 10 $]] seconds after the flash fires. How far from you was the lightning struck?

The distance between you and the thunder is about


[[$ s ≈ $]] km.

c) You stand in front of a stone wall and let out a loud exclamation towards the stone wall. The echo will reply to you in [[$ 13 $]] seconds. Assess the distance between you and the stone wall?

The distance between you and the stone wall is:


[[$ s ≈ $]] km.