Can you explain why this is incorrect and how to get the proper calculations for it

Required information PA6-3 (Static) Recording Sales with Discounts and Estimated and Actual Returns, and Analyzing Gross Profit Percentage [LO 6-4, LO 6-5] [The following information applies to the questions displayed below.] Hair World Incorporated is a wholesaler of hair supplies. Hair World uses a perpetual inventory system. The following transactions (summarized) have been selected for analysis: $ 51,200 a. Sold merchandise for cash (cost of merchandise $28,797). b. Received merchandise returned by customers as unsatisfactory (but in perfect condition) for cash refund (original cost of merchandise $220). c. Sold merchandise (costing $4,750) to a customer on account with terms n/60. d. Collected half of the balance owed by the customer in (c). e. Granted a partial allowance relating to credit sales the customer in (c) had not yet paid. f. Anticipate further returns of merchandise (costing $140) after year-end from sales made during the year. 250 10,000 5,000 160 350 Required: 1. Compute Net Sales and Gross Profit for Hair World. Answer is complete but not entirely correct. Net Sales $ 60,790 Gross Profit $ 31,773