Given the following data, calculate the cost of ending inventory using the FIFO costing method: 1/1 Beginning inventory 45 units at $10 per unit 2/25 Purchases 40 units at $12 per unit 6/15 Purchases 30 units at $13 per unit 9/20 Purchases 12/31Ending inventory 40 units 25 units at $14 per unit O a. $400 O b. $560 O c. $545 O d. $480