1. The discrete random variables $X$ and $y$ have joint distribution \begin{tabular}{1ccc} & $x=1$ & $x=2$ & $x=3$ \hline$y=1$ & $3 / 12$ & $1 / 12$ & $3 / 12$ $y=2$ & $1 / 12$ & $3 / 12$ & $1 / 12$ \end{tabular (a) (4 points) Calculate $\operatorname{Cov}(X, Y)$. Show your work. (b) ( 2 points) Are $X$ and $y$ independent? Prove your answer. SP. AS374