 Complete the following phrase:  At the 2012 Summer Olympics in London, Dwyer swam his first race in the mens 400-meter freestyle. In the heats of the 400-meter freestyle, Dwyer achieved a personal best of 3:46.24 with his prior being 3:47.83 to qualify for the final. In the final of the 400-meter freestyle, Dwyer placed fifth with a time of 3:46.39, slightly slower than the time he posted in the heats. In his second and last event, the 