hi, i need help with this question

using speherical polar coordinates $\displaystyle (r,\theta, \phi)$

verify that the vector $\displaystyle F =r^-2e_r$ is solenoidal i.e. $\displaystyle \nabla \wedge F =0$, how do i express $\displaystyle F$ in vector form, and how do i go about answering this question