A boy receives the echo of his clap reflected by a nearby hill 0.8s later. If the speed of sound in air is 340ms\(^-1\), how far is he from the hill?
66m
136m
264m
528m
Correct answer is B
2 × Distance = speed × time
2 × Distance = (340) × (0.8)
= 272/2
Distance = 136m