As of October 2021, the risk-free rate, represented by annual return on 20-year treasury bond was 3.3 percent, beta value for Walmart stood at 0.51, while the average market return, represented by average annualized total return for the S&P 500 index over the past 90 years, is 9.8 percent. From the balance sheet, the total shareholder equity for Walmart for the 2021 fiscal year was $77.87 billion (E), and the long term debt stood at $36.83 billion (D). Required: a. Calculate of the cost of overall capital for Walmart?