NVIDIA Corporation reported the following financial information for the year ending January 31, 2023:

• Total Assets: $200 billion
• Total Liabilities: $50 billion
• Shareholders' Equity: $150 billion

a) Calculate the debt-to-equity ratio. b) Determine the return on assets (ROA), assuming the net income for the year is $20 billion. c) Compute the return on equity (ROE), assuming the net income for the year is $20 billion.