The Dimitros Company records the following transactions during September 2018: Cash sales to customers totaling $6,800. Credit card sales to customers totaling $21,500. The credit card fee to the merchant is 3.0%. The credit card companies have paid all amounts due for September. A $3,000 sale on account to a long-time customer with terms of 2/10, n/30. The sale is made on September 5. The customer pays the invoice on September 14. A customer returns product they had purchased last month for $450. Dimitros accepts the return and gives the customer a cash refund. Calculate the following amounts: a. Service charge expense for credit card sales a. b. Sales discount (contra-revenue) for sales on account c. Sales returns (contra-revenue) d. Gross sales revenue e. Net sales revenue f. Net cash collected from sales