Frolic Corporation has budgeted sales and production over the next quarter as follows: Sales in units Production in units July August September 41,000 53,000 ? 42,100 53,300 57,650 The company has 4,200 units of product on hand at July 1. 10% of the next month's sales in units should be on hand at the end of each month. October sales are expected to be 72,500 units. Budgeted sales for September would be (in units)