Let F be a vector field on R^3. Suppose that F has divergence
∇·F=x^2 +y^2 +z^2.
Let S1 be the unit sphere (x^2 + y^2 + z^2 = 4), oriented outward, and let S2 be the sphere of radius 9 centered at the origin, also oriented outward. Suppose that the flux of F through S1 is 3018. Calculate the flux of F through S2.