I'm trying to learn them. I don't want just answer so please explain me these question with some reasons

Use the following information to answer the three questions below: A firm has an opportunity cost of capital of 15%, it can borrow long term debt at a cost of 10%, its marginal tax rate is 50% and it has an expected cash flow to the firm of 150 Cin perpetuity). The market value of its equity and debt are 900 and 600, respectively