Suppose That the Flux of a Smooth Vector Field $\vec { F}$

Essay

Suppose that the flux of a smooth vector field $\vec { F}$ out of a sphere of radius r centered at the origin is $a r + b r ^ { 2 }$ where a and b are constants.If ${ \vec { F } } = \operatorname { Curl } { \vec { G } }$ for a smooth vector field $\vec { G } ,$ find the values of a and b.