Can I please have your assistance with the problems below?

A light ray propagates in Material 1 with index of refraction I n1 = 1.23, strikes an interface, then passes into Material 2 with index of refraction n2 = 1.37. The angle of incidence at : the interface is 01 = 30.7\". I I l Determine the angle of refraction 92. Material 1 The speed of light c in a vacuum is 2.997 x 108 m/s. Given that the index of refraction in benzene is 1.501, what is the speed of light vbmene in benzene? Given that the index of refraction in crystalline quartz is 1.544, what is the speed of light verysmm gum in crystalline quartz