Assume that $f^{\prime}(x)$ is continuous everywhere and that $f(x)$ has one and only one critical value at $x=0$. Use the additional given information to determine whether $y=f(x)$ attains a relative minimum, a relative maximum, or neither at $x=0 .$ Explain your reasoning. Sketch a possible graph in each case.
$f(0)=1, f(5)=5,$ and $f(-5)=0$