Perpetual Inventory Using Weighted Average Beginning Inventory, purchases, and sales for H76 are as follows: July 1 Inventory 300 units at $120 210 units 12 Sale 23 Purchase 360 units at $135 26 Sale 330 units a. Assuming a perpetual inventory system and using the weighted average method, determine the weighted average unit cost after the July 23 purchase. per unit b. Assuming a perpetual inventory system and using the weighted average method, determine the cost of the merchandise sold on July 26 c. Assuming a perpetual inventory system and using the weighted average method, determine the inventory on July 31