Question

Use the divergence theorem to evaluate the flux of F across S) if F=3xyi+3yzj+6xzk and S is the surface of the region in the first octant bounded by x = 0, y = 0, below by z = 6, and above by z=9−x2−y2.

here's what I have:
divF=3y+3z+6x
I'm a bit confused on the bounds:
theta would be between 0 and pi/2,
r would be between 0 and 3?,
z would be between 6 and (9-r^2)?