Because it happens to be a cylinder.

So the length of the rectangle in the figure is 3. 14x,

Then: x+3. 14x= 16.56.

Solution: x=4

The height of the cylinder is 2x = 2 * 4 = 8cm.

The volume of the cylinder is 3.14 * (4/2) 2 * 8 =100.48.