Light passes from medium A into medium B at an angle of incidence of 30o. The index

Question:

Light passes from medium A into medium B at an angle of incidence of 30o. The index of refraction of A is 1.5 times that of B.
(a) What is the angle of refraction?
(b) What is the ratio of the speed of light in B to the speed of light in A?
(c) What is the ratio of the frequency of light in B to the frequency of light in A?
(d) At what angle of incidence would the light be internally reflected?