d= 15 in

Find the base of the cylinder. If given the radius, then base area of the circle is pi(r^2) = Square the radius then multiply by pi.

Then multiply this circle - which is the base of our cylinder - by the height. V = b x h = [pi(r^2)] x h = Square the radius then multiply by pi then by the height. I can't tell if d is the height or radius or diameter. Diameter is double the radius. SO divide diameter to get radius and vwhala.
Example:
radius = r = 11in
height = distance = d =15 in
Volume = circle area x height = pi(121) x 15 = 5702.0
(Tenth place it 0.x
Hundreth is 0.0x
Thousandth is 0.00x
etc.)
Now add the units. We multiplied in by in by in. This gives us in^3 or inches cubed.