please help me solve these questions with explanation !!!

12. A risky portfolio that pays a 15% rate of return with probability 60% or a 5% return with probability 40% and a T-bill paying 6%. The risk premium on the risky investment is A. 11 percent B. 1 percent. C. 9 percent. D. 5 percent. For the following 5 questions: You invest $100 in a risky asset with an expected rate of return of 12% and a standard deviation of 15% and a T-bill with a rate of return of 5% and E(U)=E(r) - 0.5A0 13. What percentages of your money must be invested in the risky asset and the risk-free asset, respectively, to form a portfolio with an expected return of 9%? A. 57% and 43% B. 75% and 25% C. 43% and 57% D. cannot be determined 14. What percentages of your money must be invested in the risky asset and the risk-free asset, respectively, to form a portfolio with a standard deviation of 9%? A. 30% and 70% B. 70% and 30% C. 40% and 60% D. None of above 15. A portfolio that has an expected outcome of $115 is formed by A. investing $100 in the risky asset. B. investing $80 in the risky asset and $20 in the risk-free asset. C. borrowing $43 at the risk-free rate and investing the total amount ($143) in the risky asset. D. borrowing $33 at the risk-free rate and investing the total amount ($133) in the risky asset. 16. The slope of the CAL formed with the risky asset and the risk-free asset is equal to A. 0.3667. B. 0.6543 C. 0.4667 D. None of above 17. Suppose your risk aversion factor is 9. What weight would you assign to the risky asset? A. 0.3687 B. 0.6543 C. 0.4667. D. None of above