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 260 units. Beginning Inventory Purchase Purchase Date January 1 January 15 January 24 Units 100 360 240 Unit Cost Total Cost $ 75 $ 7,500 95 115 34,200 27,600 Required: 1. 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