Kathy owes $3650 in 7 years and $13150 in 12 years. Fortunately, Kathy won a state lottery and wanted to pay off both obligations at the end of 4 year(s). By mutual agreement with the lender, she was allowed to settle both debts with a single payment at the end of 4 years based on a simple interest rate of 16%. Determine the amount of this single payment. $