Simple math.
Volume of a cylinder is equal to pi times radius squared times height.
or simply
V = π r2 h,
Since diameter is given, we need to find the radius first by dividing diameter by 2.
or
r = d/2
therefore
r is 5 inches
We can now compute for the volume.
Anyway, pi is merely equal to 3.14
So we have,
V = (3.14) (5)^2 (12)
= 3.14 * 25 * 12
= 3.14 * 300
therefore
Volume ≈ 942 in^3
Volume of the right cylinder is 942 in^3
I hope it helps