3. Consider the \"ice-cream cone\" region between the graphs of z : V (1 / 3X32 + yz) and z : V4 m2. We want to nd the center of mass of this region, with density function 6(3, 3;, z) = z. (a) (1 Point) Explain (in a few sentences) why 5: = 37 = 0 (in other words - why the center of mass lies on the z-axis). Hint: Be careful - there are several symmetry conditions that must be checked here. Be as methodical and clear as you can. (b) (1 Point) Use a triple integral to nd 2 - the z-coordinate of the center of mass. M II