ExxonMobil Corporation has the following data for its capital structure as of December 31, 2023:

10. 
    
    • Total Debt: $90 billion
    • Total Equity: $110 billion
    • Cost of Debt: 4%
    • Cost of Equity: 8%
    • Tax Rate: 25%

Requirements:

10. 
    
    5. Calculate the debt-to-equity ratio.
    6. Determine the weighted average cost of capital (WACC).
    7. Analyze the impact of an increase in the cost of debt to 5%.
    8. Compute the optimal capital structure.
    9. Suggest ways to improve ExxonMobil’s capital structure.