FDM Company uses a perpetual inventory system. It entered into the following purchases and sales transactions for March. (For specific identification, the March 9 sale consisted of 80 units from the beginning inventory and 340 units from the March 5 purchase; the March 29 sale consisted of 40 units from the March 18 purchase and 120 units from the March 25 purchase.) Required 1. Compute cost of goods available for sale and the number of units available for sale. 2. Compute the number of units in ending inventory. 3. Compute the cost assigned to ending inventory using (a) FIFO, (b) LIFO, (c) weighted average, and (d) specific identification. (Round all amounts to cents.) 4. Compute gross profit earned by the company for each of the four costing methods in part 3