As a junior investment analyst in a London-based hedge fund, you decide to use Multi-factor model to select the stock and construct your investment portfolio. The following table shows the variance-covariance matrix of your selected stocks. Suppose that you have invested 40% in stock Y, 40% in Stock Z, and 20% in Stock X, and the expected return for Stock Y, Z, and X are 16.21%, 14.8% and 7.83% respectively. You are required to calculate portfolios expected return and standard deviation.

Stock X Stock Y Stock Z Stock X 0.0256 0.0256 0.0168 Stock Y 0.0400 0.0150 Stock Z 0.0225