Angler fish emit light through bioluminescence. An angler fish is swimming in a fish tank that has a film on the inside of the glass. The water in the tank has an index of refraction of 1.10, the film

Angler fish emit light through bioluminescence. An angler fish is swimming in a fish tank that has a film on the inside of the glass. The water in the tank has an index of refraction of 1.10, the film has an index of refraction of 1.21 and the glass has an index of refraction of 1.40. The film is 90.0 nm thick, and is such that the light reflecting back at the angler fish has been minimized. Find the wavelength of the angler fish’s light.