The following data is available for an item of JNC Inc. for the month of October: October 1 Inventory 15 units at $10 each October 15 Purchase 30 units at $18 each October 31 Purchase 24 units at $15 each During the month, 32 units were sold Using the first-in, first-out (FIFO) periodic inventory method, what is JNC Inc.'s cost of ending inventory at October 31? O a. $594 O b. $630 O c. $480 O d. $620