Courtney Company uses a periodic inventory system. The following data were available: beginning inventory, 1,200 units at $30; purchases, 3,600 units at $34; operating expenses (excluding income taxes), $90,000; ending inventory per physical count at December 31, 850 units; sales price per unit, $70; and average income tax rate, 30%.

Required:

1. 1. Complete the income statements and the cost of goods sold calculation under the FIFO, LIFO, and weighted average costing methods.
2. 2-a. Between FIFO and LIFO, which method is preferable in terms of maximizing income from operations, if costs are rising?
3. 2-b. Between FIFO and LIFO, which method is preferable in terms of minimizing income taxes, if costs are rising?
4. 3-a. Between FIFO and LIFO, which method is preferable in terms of maximizing income from operations, if costs are falling?
5. 3-b. Between FIFO and LIFO, which method is preferable in terms of minimizing income taxes, if costs are falling?

Please help.