An Oil Layer That Is 4

Multiple Choice

An oil layer that is 4.0 cm thick is spread smoothly and evenly over the surface of water on a windless day. The angle of refraction in the water for a ray of light that has an angle of incidence of 45^o as it enters the oil from the air above is 32^o. (The index of refraction for oil is 1.15, and for water it is 1.33.) If the layer of oil becomes thicker, the angle of refraction in the water

A) increases.
B) stays the same.
C) decreases.
D) More information is needed to work out the answer.