PLEASE COMPUTE B! I WOULD LIKE TO KNOW THE WAY OF CALCULATING IT

Consider the following information. The CAPM assumptions are valid. Beta Portfolios Market A E(r) % 5 St. Dev. % 6 1 0 B 7.5 0.5 6 a. Compute the beta of portfolio C. Justify. b. Compute the standard deviation of portfolio C knowing it is an efficient portfolio. c. What is the expected return of portfolio B? Is portfolio B an efficient portfolio? d. Please explain if two risky assets can have the same total risk (measured by the standard deviation return (maximum 5 lines)