Chapter 4.2, Problem 2QCE

Suppose that $f$ is defined everywhere and $x=2,3,5,7$ are critical points for $f$ . If $f^{\prime }\left(x\right)$ is positive on the intervals $\left(-\infty ,2\right)$ and $\left(5,7\right),$ and if $f^{\prime }\left(x\right)$ is negative on the intervals $\left(2,3\right),\left(3,5\right)$ , and $\left(7,+\infty \right),$ then $f$ has relative maxima at $x=\text{\_\_\_\_\_\_\_}$ and $f$ has relative minima at $x=\text{\_\_\_\_\_\_\_\_}$ .