Need help with 3 and 4.

Montoure Company uses a perpetual inventory system. It entered into the following calendar-year 2015 purchases and sales transactions. Required: Compute cost of goods available for sale and the number of units available for sale. Compute the number of units in ending inventory. Compute the cost assigned to ending inventory using FIFO, LIFO, weighted average, and specific identification. For specific identification units sold consist of 700 units from beginning inventory, 250 from the February 10 purchase, 150 from the March 13 purchase, 140 from the August 21 purchase, and 195 from the September 5 purchase. (Round your average cost per unit to 2 decimal places.) Compute gross profit earned by the company for each of the four costing methods. (Round your average cost per unit to 2 decimal places.)