Use this data (or select pieces of the data) to determine : A) OSK's After Tax Cost of Debt B) OSK's Cost of Equity C) OSK's WACC ( weighted average cost of capital ).

SharesoutstandingSharepriceCostofnewdebtOptimalD/EratioBetaoffirmMarketRiskPremiumRiskFreeRateTaxrate69,000,000$89.768%0.501.4210%5%21%