1. 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.

2. Since 2006, major motion pictures have been released in the DVD format rather than the older VHS format. The basic principle behind DVD’s and CD’s is based on the reflection of light. Using the Internet, explain how a DVD player is able to read the information stored on a DVD.