EX2: On September 1, Reid Supply had an inventory of 15 backpacks at a cost of $20 each. The company uses a perpetual inventory system. During September, the following transactions and events occurred. Sept. 4 Purchased 80 backpacks at $20 each from Hunter, terms 2/10, n/30. 6 Received credit of $120 for the return of 6 backpacks purchased on Sept. 4 that were defective. Sept. 9 Sold 40 backpacks for $25 each to Oliver Books, terms 2/10, n/30. Sept. Sept. 13 Sold 15 backpacks for $25 each to Heller Office Supply, terms n/30. Sept. 14 Paid Hunter in full, less discount