8.The units of an item available for sale during the year were as follows: January 11 Inventory 60 units @ $145 February 27 Purchase 90 units @ $150 November 21 Purchase 75 units @ $154 There are 48 units of the item in the physical inventory at December 31. The periodic inventory system is used. a. Determine the inventory cost by the first-in, first-out method. $ b. Determine the inventory cost by the last-in, first-out method. $ c. Determine the inventory cost by the average cost method. $