Supplement C Recording Purchases and Sales Using a Perpetual and Periodic Inventory System Misty Company reported beginning inventory of 100 units at a unit cost of $20. It engaged in the following purchase and sale transactions during 2011: Jan. 14 Sold 20 units at unit sales price of $47.50 on open account. April 9 Purchased 15 additional units at unit cost of $20 on open account. Sept. 2 Sold 45 units at sales price of $50 on open account. At the end of 2011, a physical count showed that Misty Company had 50 units of inventory still on hand. Required: Record each transaction, assuming that Misty Company uses (a) A perpetual inventory system and (b) A periodic inventory system (including any necessary entries at the end of the accounting period on December 31).