Combine independent random variables and normal distributions
Give exact values except where a probability is explicitly requested to four decimal places. In N(μ,σ²), the second parameter is the variance
X and Y are independent, with the following means and variances
\[E(X)=1,\quad E(Y)=-2,\quad \operatorname{Var}(X)=3,\quad \operatorname{Var}(Y)=3,\quad W=(2)X+(-1)Y+(-2)\]