Answer:
The firm's weighted average cost of capital if the tax rate is 34 percent is 12.69%
Explanation:
total assets = common stock value + preferred stock value + debt
          = 23000*57 + 6000*48 + 350000*102%
          = 1956000
WACC
= (common stock value/total assets) * common stock rate of return
+ (preferred stock value/total assets) * preferred stock rate of return
+ (debt value/total assets) * yield to maturity of debt * (1-tax rate)
= (1311000/1956000)*14.2% Â + (288000/1956000)*7% Â + (357000/1956000)*8.49*(1 - 34%)
= 12.69%
Therefore, The firm's weighted average cost of capital if the tax rate is 34 percent is 12.69%