A Light Ray in Air Strikes a Glass Surface with an Angle

Multiple Choice

A light ray in air strikes a glass surface with an angle of incidence of 30.0 $^{\circ}$ .The angle of refraction in the glass is 20.0 $^{\circ}$ .What is the index of refraction of the glass?

A) 1.67
B) 1.55
C) 1.52
D) 1.46
E) 1.24