3. Lump Sum: What is the future value of $2,400 in 17 years assuming an interest rate of 7.9 percent compounded semiannually? 4. Annuity: One of your customers is delinquent on his accounts payable balance. You've mutually agreed to a repayment schedule of $500 per month. You will charge 1.5 percent per month interest on the overdue balance. If the current balance is $18,000, how long will it take for the account to be paid off