Let $Sbe$ the cube with side length $9,$ faces parallel $to$ the coordinate

planes, and centered $at$ the origin.

Enter the exact answers.

$(a)$ Calculate the total flux $of$ the constant vector field

vec$(v)=-$vec$(i)+9$vec$(j)+$vec$(k)$ out $ofSby$ computing the flux through each face

separately.

Total flux $=$

$(b)$ Calculate the flux out $ofS$ for any constant vector field

vec$(v)=$avec$(i)+$bvec$(j)+$cvec$(k)$

Total flux $=$