You invest $1,800 in a complete portfolio. The complete portfolio is composed of a risky asset with an expected rate of return of 12% and a standard deviation of 15% and a Treasury bill with a rate of return of 4%. How much of your complete portfolio should be invested in the risky portfolio if you want your complete portfolio to have a standard deviation of 9%. A. 11% B. 26% C. 60% D. 8%