Answer
$96\pi$
Work Step by Step
Since the cross section consists of two of the triangles, we find the equation for volume:
$V = (2/3)(\pi)(r^2)(h)$
We know that the values of 6 are what are being rotated, so we obtain that r=6. Thus:
$V = (2/3)(\pi)(6^2)(4) = 96\pi$
