Perpetual Inventory Using LIFO Beginning inventory, purchases, and sales for Item PK95 are as follows: March 1 Inventory 82 units @ $33 5 Sale 66 units 11 Purchase 91 units @ $37 21 Sale 76 units Assuming a perpetual inventory system and using the last-in, first-out (LIFO) method, determine (a) the cost of merchandise sold on march 21 and (b) the inventory on march 31. a. Cost of merchandise sold on July 21 $ b. Inventory on July 31 $