please solve part c and d correctly

Part 4 Projects and Their Valuation c. If the firm's bonds earn a return of 12%, then what would be your estimate of t, using the own-bond-yield-plus-judgmental-risk-premium approach? (Hint: Use the midpoint of the risk premium range.) d. On the basis of the results of parts a through what would be your estimate of Shelby's cost of equity? Part 4 Projects and Their Valuation c. If the firm's bonds earn a return of 12%, then what would be your estimate of t, using the own-bond-yield-plus-judgmental-risk-premium approach? (Hint: Use the midpoint of the risk premium range.) d. On the basis of the results of parts a through what would be your estimate of Shelby's cost of equity