3. Two children sit on a see-saw which is 3 m long and pivoted on an axis at its center. The first child has a mass mi of 25 kg and sits at the left end of the see-saw, while the second child has a mass m2 of 50 kg and sits somewhere on the see-saw to the right of the pivot point. 3 m O 12 m z m1 At what distance r2 from the pivot point should the second child sit to keep the see-saw horizontal? 2023