xz dS, S is the part of the plane 2x+ 2y + z = 4 that lies in the first octant x dS, S is the triangular region with vertices (1, 0, 0), (0, -2, 0), and (0, 0, 4) y dS, S is the surface z = 2/3 (x3/2 + y3/2), 0 x 1, 0 y 1 x2z2 dS, S is the part of the cone z2 = x2 + y2 that lies between the planes z = 1 and z = 3