Petersen Book Store entered into the transactions listed below Prepare Petersen s necessary entries, assuming use of the perpetual inventory system July 6 Purchased $1,600 of merchandise on credit terms N30 8 Returned $100 of the items purchased on July 6. 9 Paid freight charges of $90 on the items purchased July 6. 19 Sold merchandise on credit for $4.400 terms 1/10, 1/30. The merchandise had an inventory cost of $2,700. 22 of the merchandise sold on July 19, $300 of it was retumed. The items had cost the store $150