Addison, Inc. uses a perpetual inventory system. The following is information about one inventory item for the month of September Sep. 1 4 10 Inventory Sold Purchased Sold Purchased 20 units at $20 10 units 30 units at $25 20 units 10 units at $30 17 30 If Addison uses LIFO, the cost of the ending merchandise inventory on September 30 is a. $750 b. $700 c. $800 d. $650