Aggregate Slippage Over a Poisson Number of Orders

Let $X_1,X_2,\dots$ be i.i.d. increments with $E[X_i]=2$ and $\mathrm{Var}(X_i)=3$. Let $N$ be independent of the increments and distributed as Poisson(4). For the stopped sum $S_N=\sum_{i=1}^N X_i$, compute $E[S_N]$ and $\mathrm{Var}(S_N)$.