One bright summer day a swimmer is floating with her head just above the surface of a large lake where the water has index of refraction n = 1.38. Nearby she sees a tall wooden post emerging from the water. When she looks into the water at just the right angle she can see the bottom of the post, which is embedded in the lake bottom, a distance h = 5.60 meters below the water's surface. As she floats away from the post, eventually she can no longer see the bottom of it. At what distance from the post does this occur?