Find the Volume of the Described Solid $\pi$ B) 9 $\pi$ C) 36

Multiple Choice

Find the volume of the described solid.
-The solid lies between planes perpendicular to the x-axis at x = - 3 and x = 3. The cross sections perpendicular to the x-axis are semicircles whose diameters run from to

A) 72 $\pi$
B) 9 $\pi$
C) 36 $\pi$
D) 18 $\pi$