Marmara University Copy Center buys three copier machines that each have a useful life of seven years and a salvage value of $1000/copier machine. A sinking fund is established to replace all the machines at the end of 7 years. The replacement cost will be $6,000/copier machine. If equal payments are made into the fund at the end of every 6 months and the fund earns interest at the rate of 12% compounded semiannually, what should each payment be?