A swimmer floats on the surface of a completely filled 10-foot deep pool for 5 seconds. He then takes 3 seconds to swim to the bottom of the pool and 2 seconds to return to the surface, where he then floats for another 5 seconds. After that, his watch slips off and he swims halfway to the bottom to grab it. It took him 1 second to grab the watch and another 1 second to swim back to the surface. Draw a graph that models the swimmer's depth below the water's surface over time.