Adiver shines a flashlight upward from beneath the water at a 35.2° angle to the vertical. at what angle does the light leave the water?

We can solve the problem by using Snell's law:

where 
is the refractive index of the first medium (in this case, air, so )
is the refractive index of the second medium (in this case, water, so )
is the angle of incidence of the light, with respect to the vertical, so 
is the angle of refraction of the light inside the water, with respect to the vertical

Re-arranging the equation and using the data of the problem, we can find the the angle of refraction of the light inside the water: