Answer:
February 9, merchandise purchased on account:
Dr Merchandise inventory 57,000
Cr Accounts payable 57,000
March 7, merchandise sold on account
Dr Accounts receivable 79,000
Cr Sales revenue 79,000
Dr Cost of goods sold 57,000
Cr Merchandise inventory 57,000
Explanation:
Since we are not told the date when the company pays for the purchased merchandise, we can assume any date of February to record the payment:
Dr Accounts payable 57,000
Cr Cash 57,000
The same for the collection of the sales account:
Dr Cash 79,000
Cr Accounts receivable 79,000
