The units of Manganese Plus available for sale during the year were as follows: Mar. 1 Inventory 25 units @ $29 $725 June 16 Purchase 32 units @ $31 992 Nov. 28 Purchase 37 units @ $37 1,369 94 units $3,086 There are 14 units of the product in the physical inventory at November 30. The periodic inventory system is used. Round answers to the nearest whole dollar. a. Determine the inventory cost by the FIFO method. $ b. Determine the inventory cost by the LIFO method. c. Determine the inventory cost by the average cost methods