Let ${ \vec { F } } = x ( 1 + z ) \vec { i } + 2 y ( 1 + z ) \vec { j }$

Essay

Let ${ \vec { F } } = x ( 1 + z ) \vec { i } + 2 y ( 1 + z ) \vec { j }$ Find the flux of $\vec { F }$ across the parametric surface S given by x = s cos t, y = s sin t, z = s, for 1 $\le$ s $\le$ 2, 0 $\le$ t $\le$ 2 $\pi$ , oriented downward.