need help solving

E6-15 Inventory by three methods; cost of goods sold e urits of an item available for sale during the year were as follows: 21 units at $1,800 29 units at $1,950 10 units at $2,040 15 units at $2,100 Jan. 1 May 15 Aug.7 Nov. 20 Inventory Purchase Purchase Purchase There are 18 units of the item in the physical inventory at December 31. Determine the cost of ending inventory and the cost of goods sold by three methods, presenting your answers in the following form: Ending Inventory Cost of Goods Sold Inventory Method a. First-in, first-out b. Last-in, first-out C. Weighted average