A lender providing a loan of $7.5 million requires semi-annual payment of interest at a nominal rate of 8.8% per year, and repayment of the $7.5 million principal at the end of 13 years. The borrower plans to accumulate that principal for repayment at the end of 13 years using level semi-annual deposits into a sinking fund that earns interest at a nominal rate of 4.7% per year when compounded semiannually. What is the borrower's total cash outlay every 6 months?