39. You take out a consumer loan at your credit union for new insulated windows for your house. The total installed cost is $8,250, of which you pay 20% down. The balance is to be paid in 71 equal monthly payments, with a finance charge equal to 7.5% simple interest on the outstanding balance. Find the approximate annual percentage rate (APR), to the nearest tenth of a percent.
a. 18.4%
b. 14.8%
c. 15.0%
d. 25.3%