Answer: False; a cylinder is 3 dimensional, with 2 of the dimensions being the same.
Step-by-step explanation:
Think of a 3D rectangular block. To find the volume we compute length*width*height. Therefore, we need 3 pieces of info to find the volume of the block.
However, a cylinder has its "length" and "width" as the same thing (both equal to the diameter). Effectively we have 2 unique pieces of info that is enough to find the volume of the cylinder.
Side note:
radius = (diameter)/2