a$.$ Calculate the average rate of return for each stock during the $5-$year period.

b$.$ Suppose you had held a portfolio consisting of $50\%$ of Stock A and $50\%$ of Stock B$.$ What would have been the realized rate of return on the portfolio in each year? What would have been the average return on the portfolio during this period?

c$.$ Calculate the standard deviation of returns for each stock and for the portfolio.

d$.$ If you are a risk$-$averse investor, then, assuming these are your only choices, would you prefer to hold Stock A$,$ Stock B$,$ or the portfolio? Why?

You have observed the following returns over time:

$\backslash$table$[[$Year$,$Stock X$,$Stock Y$,$Market$],[2009,14\%,13\%,12\%$