Cullumber Corp. uses a perpetual inventory system. The company had the following inventory transactions in April: April 3 Purchased merchandise from Sheffield Ltd. for $23,520, terms n/30, FOB shipping point. 6 The appropriate company paid freight costs of $588 on the merchandise purchased on April 3. 7 Purchased supplies on account for $4,200. 8 Returned merchandise to Sheffield and received a credit of $2,940. The merchandise was returned to inventory for future resale. 30 Paid the amount due to Sheffield in full. 1. The cost of the merchandise sold on April 3 was $15,960. Sheffield expected a return rate of 15%. 2. The cost of the merchandise returned on April 8 was $1,932. 3. Sheffield uses a perpetual inventory system.