The units of an item available for sale during the year were as follows: January 1, Beginning Inventory, 6 units at $41. March 24, Purchase, 12 units at $40. November 7. Purchase, 10 units at $43. There are 18 units of the item in the physical inventory at December 31 . The periodic inventory system is used. Determine the inventory cost at December 31 using the FIFO method