a company had the following purchases and sales during its first year of operations: purchasessales january:30 units at $22022 units february:40 units at $22525 units may:35 units at $23029 units september:32 units at $23528 units november:29 units at $24030 units on december 31, there were 32 units remaining in ending inventory. using the perpetual lifo inventory costing method, what is the cost of the ending inventory? (assume all sales were made on the last day of the month.)