1. Determine the centroid of the area bounded by the y - axis, the x - axis, and the curve x2 + y - 4 = 0. 2. Determine the centroid of the area bounded by x2 - y = 0 and x - y = 0. 3. Determine the centroid of the area bounded by 2(y2 + 4) - 2x - 8 =0 and 8y + x2 = 0. 4. What is the volume in the first octant bounded by x2 + y - 4 = 0 and z = x. Use a triangular element