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Sanjeev is paid on a graduated commission scale. For the first $20,000 of sales his commission is 3.50%. On the next $15,000 he receives 6% commission, and 8.50% for all sales after that. What were Sanjeey's sales in a month when he is paid $3,980? For full marks your answer(s) should be rounded to the nearest cent. 10:32 am