Transform the following vectors into spherical coordinates and

Transform the following vectors into spherical coordinates and then evaluate them at the indicated points:
(a) A = xy2 + yxz + z4 at P1 (1 – 1, 2),
(b) B = y(x2 + y2 + z2) – z (x2 + y2) at P2 (- 1, 0, 2),
(c) C = r cos ??????sin ??z cos ?sin ??at P3 (2, ??4, 2), and
(d) D = xy2 / x2 + y2) – yx2 / (x2 + y2) + z4 at P4 (1, – 1, 2).