How many faces does a pentagonal prism have?

It has seven faces: five sides and two ends (base and top).

A prism is the body formed by the translation (movement along a line - in this case a straight line) of a shape. There will be with two bases and as many faces as the base has sides.
Therefore, a Pentagonal Prism has 7 faces; it has 5 side faces and it has 1 'base' on the top and one 'base' on the bottom. 5+1+1=7