Amazon.com, Inc.
 Data for the year ended December 31, 2023:

Item	Amount
Total Revenue	$400,000,000
Cost of Goods Sold	$250,000,000
Selling, General, and Administrative Expenses	$100,000,000
Income Tax Expense	$30,000,000
Net Income	$20,000,000

1. Calculate Amazon's operating profit margin.
2. Determine Amazon's effective tax rate.
3. Discuss the impact of cost of goods sold on Amazon's gross profit.
4. Explain how Amazon recognizes revenue from sales.
5. Evaluate Amazon's profitability using the return on equity (ROE) ratio.