Transaction for the month of March

The following transactions for the month of March have been journalized and posted to the proper accounts. Mar. 1 The business received $9,000 cash and issued common stock to stockholders. Mar. 2 Paid the first month's rent of $800. Mar. 3 Purchased equipment by paying $3,000 cash and executing a note payable for $5,000. Mar. 4 Purchased office supplies for $750 cash. Mar. 5 Billed a client for $10,000 of design services completed. Mar. 6 Received $8,000 on account for the services previously recorded. What is the ending balance in the Service Revenue account? $8,000 $10,000 $9,000 $19,000