You are considering investing $1,000 in a complete portfolio. The complete portfolio is composed of Treasury bills that pay 5% and a risky portfolio, P, constructed with two risky securities, X and Y. The optimal weights of X and Y in P are 70% and 30%, respectively. X has an expected rate of return of 20%, and Y has an expected rate of return of 11%. To form a complete portfolio with an expected rate of return of 15%, you should invest __________ in the risky portfolio P.

a)$1143 b)$1000 c)$569 d)$813