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Use the Divergence Theorem to find the outward flux of $\mathbf{F}$ across the boundary of the region $D$.
Wedge $\quad \mathbf{F}=2 x z \mathbf{i}-x y \mathbf{j}-z^{2} \mathbf{k}$
D: The wedge cut from the first octant by the plane $y+z=4$ and the elliptic cylinder $4 x^{2}+y^{2}=16$