Perpetual Inventory Using Weighted Average Beginning inventory, purchases, and sales for WCS12 are as follows: Oct. 1 Inventory 300 units at $8 13 Sale 175 units 22 Purchase 375 units at $10 29 Sale 280 units a. Assuming a perpetual inventory system and using the weighted average cost method, determine the weighted average unit cost after the October 22 purchase. Round your answer to two decimal places. per unit $ b. Assuming a perpetual inventory system and using the weighted average method, determine the cost of goods sold on October 29. Round your "average unit cost" to two decimal places. c. Assuming a perpetual inventory system and using the weighted average method, determine the inventory on October 31. Round your "average unit cost" to two decimal places. $