Investor A has a portfolio that provides an annual expected return of 12% with a standard deviation of 9%. You were hired as investor's A advisor, and you should indicate if there is an opportunity to increase investor's A return without increasing the portfolio volatility. What will be the maximum return of a combination of the index fund (return =16% and standard deviation of 13% ) and the risk free debt (return =5% ) that will not increase investor's A portfolio volatility? The answer is equal to 12,62%!