The units of an item available for sale during the year were as follows:Jan.1Inventory1,000 units at $120Feb.17Purchase1,375 units at $128July21Purchase1,500 units at $136Nov.23Purchase1,125 units at $140There are 1,200 units of the item in the physical inventory at December 31. The periodic inventory system is used. Determine the inventory cost by (a) the first-in, first-out method; (b) the last-in, first-out method; and (c) the weighted average cost method