I have an assignment to due and it asks for the angle of reflection, but I don't know how to get it. This is the question: "A beam of light is directed on the flat surface of a block of fused quartz (n=1.92). Part of the beam is refracted with an angle of refraction of 30°. What is the angle of reflection?" The answer is 46.9°. What's the procedure? Thanks. Hint: It is assumed that if it doesn't specify what medium the light is coming from then it is air (n=1.00).