Where does the spot of light hit the bottom of the pool?

In searching the bottom of a pool at night, a watchman shines a narrow beam of light from his flashlight, h = 1.5 m above the water level, onto the surface of the water at a point L = 2.8 m from the edge of the pool (Fig. 23-50). Where does the spot of light [...] http://bit.ly/9TSB4i