Company: Apple Inc.

Apple Inc. witnessed robust financial performance in the fiscal year ending September 30, 2023. The company generated total revenue of $400 billion, with a cost of goods sold (COGS) of $220 billion and operating expenses of $100 billion. The net income for the period was $60 billion. From this data: a) Calculate the gross profit margin. b) Determine the operating profit margin. c) Compute the net profit margin. d) Evaluate the return on assets (ROA) if the total assets amount to $800 billion.