Refer to the data provided in E4A.

In E4A. In chronological order, the inventory, purchases, and sales of a single product for a recent month are as follows.

1. Using the perpetual inventory system, compute the cost of ending inventory, cost of goods sold, and gross margin. Use the average-cost, FIFO, and LIFO inventory costing methods. (Round unit costs to the nearest cent.)
2. Explain the reasons for the differences in gross margin produced by the threemethods.

Units June 1 Beginning inventory 150 400 800 1,300 300 Amount per Unit $30 4 Purchase 12 Purchase 16 Sale 24 Purchase 36 60 39