Schrute Farm Sales buys portable generators for $ 500 and sells them for $ 760. He pays a sales commission of 5% of sales revenue to his sales staff. Mr. Schrute pays $ 4, 000 a month rent for his store, and also pays $ 2, 100 a month to his staff in addition to the commissions. Mr. Schrute sold 300 generators in June. If Mr. Schrute prepares a contribution margin income statement for the month of June, what would be his contribution margin?