In the figure, a laser positioned on a ship is used to communicate with a small two-man research submarine resting on the bottom of a lake. The laser is positioned 12 m above the surface of the water, and it strikes the water 20 m from the side of the ship. The water is 76 m deep and has an index of refraction of 1.33. How far horizontally is the submarine from the side of the ship? -I am not sure weather to use the mirror equation or not. I have tired to figure out the angle the lazer makes with the vertical and then combined that into a big triangle with height of 88 to find the horizontal distance but that didn't seem to get the right answer.