Dave Engle, a former teacher, now has a business selling supplementary educational materials such as books and computer software to parents and schools. In June, he borrowed $45,000 from his bank to buy some new educational computer games that he hopes to sell during August and September. The bank's rate is 6.25% exact simple interest as long as the time does not exceed half a year. If Dave repays everything in 120 days, how much will he pay?