If F = x i + y j, calculate the flux of F upward through the part of the surface z = 4 - x2 - y2 that lies above the (x, y) plane by applying the Divergence Theorem to the volume bounded by the surface and the disk that it cuts out of the (x, y) plane.
◦ 8π
◦ 18π
◦ 16π
◦ 14π
◦ 20π