Find the Flux $\vec { F }$ Of Through $S$ $\iint _ { S } \vec { F } \cdot \vec { N } d S$

Multiple Choice

Find the flux $\vec { F }$ of through $S$ , $\iint _ { S } \vec { F } \cdot \vec { N } d S$ , where $\vec { N }$ is the upward unit normal vector to S. $\overrightarrow { \mathbf { F } } ( x , y , z ) = 2 z \hat { \mathbf { i } } - 8 \hat { \mathbf { j } } + y \hat { \mathbf { k } }$
$S : x + y + z = 9$ , first octant

A) $- \frac { 81 } { 2 }$
B) $\frac { 81 } { 2 }$
C) $\frac { 99 } { 2 }$
D) $\frac { 93 } { 2 }$
E) $- \frac { 87 } { 2 }$