Perpetual Inventory Using LIFO Beginning inventory, purchases, and sales data for prepaid cell phones for December are as follows: Inventory Dec. 1 Purchases 4,100 units at $28 Dec. 10 Dec. 20 2,050 units at $30 1,845 units at $32 Sales Dec. 12 Dec. 14 Dec. 31 2,870 units 2,460 units 1,230 units a. Assuming that the perpetual inventory system is used, costing by the LIFO method, determine the cost of goods sold for each sale and the inventory balance af each sale, presenting the data in the form illustrated in Exhibit 4. Under LIFO, if units are in inventory at two different costs, enter the units with the HIGHER unit first in the Cost of Goods Sold Unit Cost column and LOWER unit cost first in the Inventory Unit Cost column. Schedule of Cost of Goods Sold LIFO Method Prepaid Cell Phones Date Dec. 1 Dec. 10 Dec. 12 Cost of Cost of Quantity Purchases Purchases Quantity Goods Sold Goods Sold Inventory Inventory Inventory Total Cost Quantity Unit Cost Total Cost Purchased Unit Cost Total Cost Sold Unit Cost Dec. 14 Dec. 20 Dec. 31