1. A laser produces light with a wavelength of 627 nm in vacuum. It takes 2.30 ns for the light to pass through 43 cm of an unknown transparent material. A. What is the frequency of the light in a vacuum? B. What is the speed of light in the material (kinematics, watch the units)? C. What is the index of refraction of the material? D. What is the wavelength of the light in the substance? E. How long would it take for this light to pass through 43 cm of water?