20. Calculating Loan Payments [LO2, 4] You want to buy a new sports coupe for $84,500, and the finance office at the dealership has quoted you an APR of 5.2 per- cent for a 60-month loan to buy the car. What will your monthly payments be? What is the effective annual rate on this loan? 21. Calculating Number of Periods [LO3] One of your customers is delinquent on his accounts payable balance. You've mutually agreed to a repayment schedule of $450 per month. You will charge 1.3 percent per month interest on the overdue bal- ance. If the current balance is $18,000, how long will it take for the account to be paid off? 24. Calculating Annuity Future Values [LO1] You are planning to make monthly deposits of $475 into a retirement account that pays 10 percent interest compounded monthly. If your first deposit will be made one month from now, how large will your retirement account be in 30 years? 25. Calculating Annuity Future Values [LO1] In the previous problem, suppose you make $5,700 annual deposits into the same retirement account. How large will your account balance be in 30 years? 26. Calculating Annuity Present Values [LO1] Beginning three months from now, you want to be able to withdraw $2,500 each quarter from your bank account to cover college expenses over the next four years. If the account pays .57 percent interest per quarter, how much do you need to have in your bank account today to meet your expense needs over the next four years