EX 7-4 Perpetual inventory using LIFO OBJ. 2, 3 Assume that the business in Exercise 73 maintains a perpetual inventory system, costing by the last-in, first-out method. Determine the cost of merchandise sold for each sale and the inventory balance after each sale, presenting the data in the form illustrated in Exhibit 4. PE 7-4A Perpetual inventory using weighted average Beginning inventory, purchases, and sales for H76 are as follows: Assuming a perpetual inventory system and using the weighted average method, deter. mine (a) the weighted average unit cost after the July 23 purchase, (b) the cost of the merchandise sold on July 26 , and (c) the inventory on July 31