In Problems 1-3, find the area of the indicated surface. Make a sketch in each case.
1. The part of the plane 3x + 4y + 6z = 12 that is above the rectangle in the xy-plane with vertices (0, 0), (2, 0), (2, 1), and (0.1)
2. The part of the plane 3x - 2y + 6z = 12 that is bounded by the planes x = 0, y = 0, and 3x + 2y = 12
3. The part of the surface z = (4 - y2 that is directly above the square in the xy-plane with vertices (1, 0), (2, 0), (2, 1), and (1, 1)