Answer
The ball will be unable to reach the point $x = 0$
The ball's turning point is $x = 2.0~m$
Work Step by Step
At $x = 7.0~m$, the ball has a mechanical energy of $75~J$
On the graph we can see that $U=0$ at $x = 7.0~m$
Therefore, the total kinetic energy at $x = 7.0~m$ is $K = 75~J$
On the graph, we can see that $U = 100~J$ at $x = 0$
By conservation of energy, the ball will be unable to reach the point $x = 0$ because the ball does not have enough mechanical energy.
Since the ball has a mechanical energy of $75~J$, the ball will be able to reach the point where $U = 75~J$. On the graph, we can see that $U = 75~J$ at $x = 2.0~m$
The ball's turning point is $x = 2.0~m$
