A man facing a high wall, notices that an echo is heard 4.0 seconds after he makes a sharp sound. After walking 200m directly towards the cliff, an echo is heard after 3.4 seconds. Calculate: I. the speed of sound

ii. How far he was from the wall when he made his second observation of the echo.

Which statement best describes the superposition principle? a.) if two in-phase waves arrive simultaneously at a point, their amplitudes add up b.) if two out-of-phase waves arrive simultaneously at a point, their amplitudes add up c.) if two in-phase waves arrive at a point one after another, their amplitudes add up d.) if two out-of-phase waves arrive at a point one after another, their amplitudes adds up