help please

5. Find the center of mass of three particles of equal mass located at the points (4, -2), (-3, 0), and (1, 5). 23. The linear density at any point of a rod 3 m long varies directly as the distance from a point to an ex- ternal point in the line of the rod and I'm from an end where the linear density is 2 kg/m. If the total mass of the rod is 15 kg, find the center of mass of the rod. 15. Find the length of arc of the curve x2/3 + y?/3 = 1 in the first quadrant from the point where x = = to the point where x = 1