Please explain why you choose your answer, thank you!

1. If the CAPM is used to estimate the cost of equity capital for a 10-year project, the risk- free rate is equal to the: a. the current yield for one-year T-bill. b. the average yield of one-year T-bill anticipated over the life of the project. c. the current yield of 10-year T-bond. d. beta times the risk-free rate. e. market rate of return. 2. The optimal capital structure is an implication of which theory? a. MM propositionI MM propositionI c. Trade-off theory (between the tax advantage of debt and the costs of financial distress) d. CAPM e. Term structure