Exercise: Opera Inc. Opera Inc. distributes CDs to retail stores and extends credit terms of 2/10, 1/30 to all its customers. At the end of May, Opera has zero balance of inventory. During the month of June the following merchandising transaction occurred. June 1 Purchased 280 CDs on account for $6 each from Sony Music FOB shipping point, terms 2/10, 1/30. The appropriate party also made cash payment for $85 for the freight on this date June 6 Returned 30 CDs to Sony Music June 7 Paid Sony Music for the purchase on June 1 June 10 Sold 150 CDs on account to B2S for $12 each. The freight term is FOB shipping point. The appropriate party made cash payment of $50 for the freight on this date June 12 Received 70 CDs returned from B2S June 15 Received the payment from B2S for the sale of June 3 June 30 Record cost of goods sold (for periodic inventory system) Required: Prepare the journal entries to record the transactions under perpetual inventory system and period inventory system