Part 3 1) Set your top medium as Mystery B. Set your bottom medium to custom and the index of refraction to 1.15. Bring the protractor out. Turn on the laser and put the angle of incidence at 40.0. Use your protractor to find the angle of refraction and record it below. 2) Using Snell's Law, calculate the index of refraction of the INCIDENT medium (Mystery B). Record it below. Show your work. (mystery B)