Suppose that you are a fund manager who manages a risky portfolio with an expected return of 11% and a standard deviation of 23%. The risk-free rate (T-bill rate) is 3%. Suppose that you have a client that prefers to invest in your risky portfolio a proportion y of his total investment budget and invest 1-y of his total budget in T-bills so that his overall portfolio will have an expected return of 7%.

a. What is the investment proportion y?

b. What is the standard deviation of the return on your clients portfolio?