Answer:
![\displaystyle r=\sqrt[3]{(3V)/(4\pi)}](https://img.qammunity.org/2021/formulas/mathematics/high-school/eav7c99km4lxn95xkmprsc460763eppxf8.png)
The last option matches the correct solution
Explanation:
Equation Solving
We have the following equation:

And it's required to solve it for r.
Solving this equation needs to perform some operations to have the r isolated from any other variables or constants.
It can be done by conveniently operating on both sides as follows:
Eliminate the denominator by multiplying by 3:

Move
to the other side by dividing by
:

Swapping sides to have r at the left side:

Finally, take the cubic root and leave r alone:
![\displaystyle r=\sqrt[3]{(3V)/(4\pi)}](https://img.qammunity.org/2021/formulas/mathematics/high-school/eav7c99km4lxn95xkmprsc460763eppxf8.png)
The last option matches the correct solution