Please help!

Big Sound, a merchandising company specializing in home computer speakers, budgets its monthly cost of goods sold to equal 50% of sales. Its inventory policy calls for ending inventory in each month to equal 40% of the next month's budgeted cost of goods sold. All purchases are on credit, and 30% of the purchases in a month is paid for in the same month. Another 10% is paid for during the first month after purchase, and the remaining 60% is paid for in the second month after purchase. The following sales budgets are set: July, $200,000; August, $140,000; September, $170,000; October, $125,000; and November, $115,000. Compute the budgeted merchandise purchases for July, August, September, and October. Compute the budgeted payments on accounts payable for September and October. Compute the budgeted ending balances of accounts payable for September and October