Find the Volume of the Described Solid $y = 6 \cos x$

Multiple Choice

Find the volume of the described solid.
-The base of a solid is the region between the curve $y = 6 \cos x$ and the $x$ -axis from $x = 0$ to $x = \pi / 2$ . The cross sections perpendicular to the $x$ -axis are squares with bases running from the $x$ -axis to the curve.

A) $3 \pi$
B) $18 \pi$
C) $9 \pi$
D) $\frac { 35 } { 4 } \pi$