Answer and Explanation:
a. The computation of the wacc is as followS;
= cost of common stock × weight of common stock + cost of debt × weight of debt × (1 - tax rate)
= 0.16 × 0.70 + 0.08 × 0.30 × (1 - 0.30)
= 0.112 + 0.0168
= 0.1288
= 12.88%
b. The after tax cost of debt is
= 0.08 × (1- 0.30)
= 0.056
So the capital should use the cost of debt