1.) What is the intensity of a sound that has an intensity level of (a) 50 dB or (b) 90 dB?
2.) A person standing 4.0 m from a wall shouts such that the sound strikes the wall with an intensity of 2.5 x 10 x 10 W/m . Assuming that the wall absorbs 20% of the incident energy and reflects the rest, what is the sound intensity level just before and after the sound is reflected?