Determining the angle of refraction between rays?

Question

A ray of sunlight is passing from diamond into crown glass; the angle of incidence is 21.00°. The indices of refraction for the blue and red components of the ray are: blue (ndiamond = 2.444, ncrown glass = 1.531), and red (ndiamond = 2.410, n crown glass = 1.520). Determine the angle between the refracted blue and red rays in the crown glass. Give your answer to two significant figures.

Answer 1

For the blue component:

sin(21) / sin(r1) = 1.531 / 2.444

sin(r1) = 34.8953 deg.

For the red component:

sin(21) / sin(r2) = 1.520 / 2.410

sin(r2) = 34.6249 deg.

Angle between them is:

34.8953 - 34.6249

= 0.27 deg.