Finance due tonight. please help, will upvote. Thanks alot!!

Navarro Corporation has no debt but can borrow at 6.5 percent. The firm's WACC is currently 8.7 percent, and the tax rate is 23 percent. a. What is the company's cost of equity? (Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.) b. If the firm converts to 30 percent debt, what will its cost of equity be? (Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.) c. If the firm converts to 55 percent debt, what will its cost of equity be? (Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.) d-1. If the firm converts to 30 percent debt, what is the company's WACC? (Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.) d-2. If the firm converts to 55 percent debt, what is the company's WACC? (Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.)