sold merchandise for cash ( cost of merchandise $40,797) $75,200

received merchandise returned by costumers as unsatisfactory ( but in perfect condition ) for cash refund (original cash of merchandise $540) $900

sold merchandise ( costing $7600) to a costumer on account with term n/60 $16,000

collected half of the balance owed by the costumer in (c) $8,000

granted a partial allowance relating to credit sales the costumer in (c) had not paid yet $256

compute the net sales and gross profit