11. a sphere of units radius is cenered at the origin. the unit normal at a point (x, y, z) on the surface of the sphere is the vector 1 (b) 1 1 (a) (x, y, 2) z

11. A sphere of units radius is cenered at the origin. The unit normal at a point (x, y, z) on the surface of the sphere is the vector 1 (b) 1 1 (a) (x, y, 2) Z (4) 12. Let r and 10 ho