The management of Kinko's has had a target capital structure of 20/80 debt-to-equity (based on market values), but is contemplating moving toward a

The management of Kinko's has had a target capital structure of 20/80 debt-to-equity (based on market values), but is contemplating moving toward a higher debt/equity  ratio as the company finances its high rate of growth.

Under M&M theory with taxes, do the following rise, fall, or remain the same as Kinko's shifts to the higher debt ratio?

1. WACC,
2. Interest rate on debt,
3. Cost of Equity,
4. Debt/(Debt + Equity)