A mutual fund manager expects his portfolio to earn a rate of return of 11 percent this year. The beta of the portfolio is 0.8. If the market risk premium is 10 percent and the risk-free rate is 4 percent, is it a good idea to invest? How could you use a stock index fund (S&P 500 index) and risk-free fund (invested in T-bills) to create a portfolio with the same risk as the manager, but a higher return?