A Flashlight Beam Makes an Angle of 60° with the Plane

Multiple Choice

A flashlight beam makes an angle of 60° with the plane of the surface of a calm lake before it enters the water.In the water what angle does the beam make with the plane of the surface? The index of refraction of water is 1.33.

A) 0°
B) 30°
C) 60°
D) 22°
E) 68°