I have sent in this question already and got the incorrect answer for part d. The answer they provided me with was 23.82%

After visiting several automobile dealerships, Richard selects the car he wants. He likes its $16,000 price, but financing through the dealer is no bargain. He has $3,200 cash for a down payment, so he needs a loan of $12,800. In shopping at several banks for an installment loan, he learns that interest on most automobile loans is quoted at add-on rates. That is, during the life of the loan, interest is paid on the full amount borrowed even though a portion of the principal has been paid back. Richard borrows $12,800 for a period of four years at an add-on interest rate of 14 percent. a. What is the total interest on Richard's loan? Total interest 7,168 b.What is the total cost of the car? Total cost 23,168 c. What is the monthly payment? Monthly payment d. What is the annual percentage rate (APR)? (Enter your answer as a percent rounded to 2 decimal places.) APR %