Oahu Kiki tracks the number of units purchased and sold throughout each accounting period but applies its inventory costing method at the end of each month, as if it uses a periodic inventory system. Assume Oahu Kiki's records show the following for the month of January. Sales totaled 330 units Units Unit Cost Total Cost Date Beginning Inventory January 1180 January 15 420 January 24 320 75 85 105 $13,500 35,700 33,600 Purchase Purchase Required: . Calculate the number and cost of goods available for sale. 2. Calculate the number of units in ending inventory. 3. Calculate the cost of ending inventory and cost of goods sold using the (a) FIFO, (b) LIFO, and (c) weighted average cost methods