Analyze the inventory valuation methods used by IBM Corporation. The following inventory data is available for the year ended December 31, 2024:

Item	Beginning Inventory ($)	Purchases ($)	Ending Inventory ($)
Product A	$50,000	$200,000	$60,000
Product B	$80,000	$150,000	$40,000
Product C	$100,000	$120,000	$80,000

Calculate the cost of goods sold and ending inventory using the FIFO, LIFO, and weighted-average methods. Discuss the impact on profitability and tax implications.