The drawing shows a rectangular block of glass (n = 1.52) surrounded by liquid carbon disulfide (n = 1.63). A ray of light is incident on the glass at point A with a = 36.0° angle of incidence. At what angle of refraction does the ray leave the glass at point B?

Please explain a way to reach the solution for this problem. I tried using the equation: n2*sin(36) / n1

pic:

http://img128.imageshack.us/img128/900/13113445ga1.png
it does not seem to work with the problems i'm working with. I may not be using the equation correctly.