Perpetual inventory Using LIFO Beginning inventory, purchases, and sales data for prepaid cell phones for May are as foliows: a. Assuming that the perpetual inventory system is used, costing by the Lifo method, determine the cost of merchandise sold for each sale and the inventory balance after each sale, presenting the data in the form lilustrated in Exhibit 4. Under LiFO, if units are in inventory at two different costs, enter the units with the HIGHER unit cost first in the Cost of Merchandise Sold Unit Cost column ond LoweR unit cost first in the Inventory Unit Cost column