There are conflicting definitions in the math world...so you need to go with the definitions presented by the district's curriculum and resources. For example, in my district, we use the definition that faces are flat surfaces (does NOT specify "polygons") of 3-d figures...therefore a cone has one and a cylinder has 2.
Another example:
Some mathematicians define a rhombus as a quadrilateral with 4 equal sides and 2 pair of parallel sides.
Others define a rhombus as a quadrilateral with 4 equal sides, 2 pair of parallel sides, AND specify that the angles are "oblique".
So where's the confusion?
Well, under the 1st definition, a square would be considered a rhombus, but under the 2nd definition, it wouldn't.
http://mathcentral.uregina.ca/QQ/dat....02/beth1.html