We will now analyze the historical returns of your chosen stocks. You may choose any time period and frequency you deem suitable, but make sure that all of your returns are reported as annualized rates. You will want to use the adjusted closing price to automatically account for the effects of dividends and splits.

Consider AAPL(Apple Inc.) and PFE(Pfizer Inc.) stocks

(a). For each stock as a well as a suitable market index, report the mean and standard deviation of returns.

(b). Find the variance-covariance matrix of the two stocks and the market index, and report the beta of each stock.