Unit 2 Exam Review Chapter 21. The energy of a photon of light is __________ proportional to its frequency and __________ proportional to its wavelength.A. directly, directlyB. inversely, inverselyC. inversely, directlyD. directly, inverselyE. indirectly, not 2. What color of visible light has the longest wavelength?A. blueB. violetC. redD. yellowE. green 3. What is the frequency […]