We start with the equation for the volume of a cone:
\[ V = \frac{1}{3} \pi r h \]
To solve for \( h \), we first want to isolate \( h \) on one side of the equation. We can do this by multiplying both sides by 3 to remove the fraction:
\[ 3V = \pi r h \]
Next, we divide both sides by \( \pi r \) to solve for \( h \):
\[ h = \frac{3V}{\pi r} \]
Thus, the correct answer is:
c. \( h = \frac{3v}{\pi r} \)