4. Compute the volume of each of the following regions.

(a) E is bounded by the surfaces x + y + z = 3, z = 0, and x2 + y2 = 1.

(b) E lies under the plane z = x + y and over the region in the xy plane bounded by the curves x = JY72, x = 2Vfj, x + y = 3.

(c) E is bounded by z = y2, X = y2 + Z2, X = 0, z = 1.

(d) E is bounded by y = x3, X = z2, Z = x2, and y = o.