The question states as follows;
"The cube root of r varies inversely with the square of s."
The general form of an inverse relationship is shown below;
[tex]y=\frac{k}{x}[/tex]Substituting the variables, we would now have;
[tex]\sqrt[3]{r}=\frac{k}{s^2}[/tex]Therefore, the third option is correct.
Also;
[tex]\begin{gathered} \sqrt[3]{r}=\frac{k}{s^2} \\ \text{Observe that}_{} \\ \sqrt[3]{r}=r^{\frac{1}{3}} \end{gathered}[/tex]Therefore, we can alo have the expression;
[tex]\begin{gathered} r^{\frac{1}{3}}=\frac{k}{s^2} \\ \text{Cross multiply, and we'll have;} \\ s^2r^{\frac{1}{3}}=k \end{gathered}[/tex]The fifth option is also correct.
ANSWER:
The third and fifth options are both correct models of the inverse relationship given.