During December, the company completed the following summary transactions.

Dec. 6 Paid $1,600 for salaries due employees, of which $600 is for December and $1,000 is for November salaries payable.

Dec. 8 Received $1,900 cash from customers in payment of account (no discount allowed).

Dec. 10 Sold merchandise for cash $6,300. The cost of the merchandise sold was $4,100.

Dec. 13 Purchased merchandise on account from Gong Co. $9,000, terms 2/10, n/30.

Dec. 15 Purchased supplies for cash $2,000.

Dec. 18 Sold merchandise on account $12,000, terms 3/10, n/30. The cost of the merchandise sold was $8,000.

Dec. 20 Paid salaries $1,800.

Dec. 23 Paid Gong Co. in full, less discount.

Dec. 27 Received collections in full, less discounts, from customers billed on December 18.

(a) Journalize the December transactions using a perpetual inventory system.