Question

02:32:00

Answer 1

The volume is given by

$V=\pi hr^2$

Since the height is 3 times the radius of the base, we can substitute $h=3r$:

$V=\pi (3r)r^2=3\pi r^3$

And we know that the volume is $24\pi$ (I'm actually assuming that there's a typo in the question, otherwise the options wouldn't match):

$24\pi=3\pi r^3 \iff r^3=8 \iff r=2$

The height is 3 times the radius, so it is

$h=2\cdot 3 = 6$