Avortex that rotates at constant angular velocity about the z-axis has velocity vector field ⃗ =−⃗ +⃗ ). (a) sketch, on a separate sheet of paper, the vector field with =1 and the vector field with =−1. then determine the speed ‖⃗ ‖ of the vortex as a function of the distance from its center, ) compute div v and curl v. div v = curl v=(c) compute the circulation of v counterclockwise about the circle of radius r in the xy-plane, centered at the origin. circulation =