Solve the all parts of following question:
Question: A thin film having an index of refraction of 1.50 is surrounded by air. It is illuminated normally by white light. Analysis of the reflected light shows that the wavelengths 360, 450, and 600 nm are the only missing wavelengths in the visible portion of the spectrum, that is, for those wavelengths, there is destructive interference.
Part A: What is the thickness of the film?
Part B: What wavelengths in the visible portion of the spectrum are brightest in the reflected interference pattern? (Enter your answers from smallest to largest.)
Part C: If this film were resting on glass that has an index of refraction of 1.60, what wavelengths in the visible spectrum would be missing from the reflected light? (Enter your answers from smallest to largest.)
I am having a hard time understanding these questions. So if you answer please explain how you found the answers.