(a) Set up a double integral for calculating the flux of the vector field $\vec{F}(x,y,z) = - 3 xz \vec{i} - 3 yz \vec{j} + z^2 \vec{k}$ through the part of the cone $z = \sqrt{x^2+y^2}$ for $0 \leq z \leq 4$, oriented upward.

Flux = $\displaystyle \iint\limits_{Disk}$ $dx \, dy$

(b) Evaluate the integral.
Flux = $\displaystyle \iint\limits_S \vec{F} \cdot d\vec{A}$ =

Hint: