1. (a) Use double integral to find the volume of the solid under the surface z = x and over the region R bounded by y = =, y = x, and x = 4. (b) Use double integral to find the volume of the solid bounded by the cylinder x2 + yz = 9 and the planes z = 0, z = 4 - y. 2. (a) Use triple integral to find the volume of the solid bounded by the surface z = vy and the planes x + y = 1, y = 0, and z = 0. (b) Use spherical coordinates to evaluate the triple integral JJJ vx2 + y2 + z2 dv where G is the solid enclosed by the hemi-sphere z = 19 - x2 - y2 and the xy-plane