Q1. A loudspeaker is placed between two observers who are 120 m apart, along line connecting them. If one observer records a sound level of 52.8 dB and the other records a sound level of 83.5 dB, how far is the speaker from each observer? Enter the longest distance first.

Q2. A thin soap film (n = 1.33) has a uniform thickness. When white light strikes the film at normal incidence, blue light (b = 440 nm) is constructively reflected. At what angle of incidence will green light (g = 560 nm) be most strongly reflected? Suppose the film has the minimum thickness that can generate these reflections. In degrees