An investment portfolio in Singapore specializes in airline stocks and contains two of them. One is Singapore Airlines (mean: 0.12 ; standard deviation: 0.02 ), and it accounts for $30 \%$ of the portfolio shares. The other airline present in the portfolio is AirAsia (mean: 0.25 ; standard deviation: 0.15 ), a higher-risk, higherreturn investment.
a. What is the expected value and the standard deviation of the portfolio if the coefficient of correlation of the two stocks is 0.5 ?
b. What will they be if the correlation is 0.2 instead?