Aball is rolled uphill a distance of 4 meters before it slows, stops, and begins to roll back. the ball rolls downhill 28 meters before coming to rest against a tree. what is the magnitude of the ball’s displacement?

The main assumption is that the ball followed the same way uphill and back, so it was at the same initial point when it rolled back 4 m.

At this moment the displacement was zero (remember that the displacement is the difference between the final position and the initial position).

From that point the ball displaced other 24 m down (28m - 4m = 24 m). And, that is the magnitude of the ball's displacement.

24 m.