Distance of the center of mass of a solid uniform cone from its vertex is $z_0$. If the radius of its base is R and its height is h then $z_0$ is equal to :

Question

$\begin{array}{1 1} \frac{3h}{4} \\ \frac{5h}{8} \\ \frac{3h^2}{8R} \\ \frac{h^2}{4R} \end{array}$