Journalize the entries for the following transactions:

a. Sold merchandise for cash, $30,000. The cost of the merchandise sold was $18,000.

b. Sold merchandise on account, $258,000. The cost of the merchandise sold was $154,800.

c. Sold merchandise to customers who used MasterCard and VISA, $160,000. The cost of the merchandise sold was $96,000.

d. Sold merchandise to customers who used American Express, $72,000. The cost of the merchandise sold was $43,200.

e. Received an invoice from National Clearing House Credit Co. for $8,800, representing a service fee paid for processing MasterCard, VISA, and American Express sales?