Use the following information to answer the questions

Case I: Capital structure $($no corporate tax$)$

Debt$-$to$-$firm value $($D$/$V$)$: $0\%$

Cost of equity: $10\%$

Cost of debt: $8\%$

Case II: Capital structure $($corporate tax$)$

Debt: $ $0$ million

EBIT: $$40$ million

Tax rate: $50\%$

Unlevered cost of capital: $10\%$

In Case I, when the debt$-$to$-$firm value $($D$/$V$)$ increases from $0\%$ to $60\%,$

Figure out WACC with zero debt. $(20$points$)$

Figure out WACC with debt of $60\%.(20$points$).$