1. 2 cases: there are three mediums first case: light travels from first medium to second, then to third. n1 = 1.1; n2 =1.6; n3 =1.9 angle of incidence before first = theta 1 angle of refraction after first = theta 2 angle of refraction after second = theta 3 second case: light travels through three mediums n1' = n1 n2' = 1.5 n3' = n3 theta 1' = theta 1 2. R = sin theta 3' / sin theta 3 what should be the value of R? 3. I keep getting 1. I donno why though?