**The volume of a pentagonal prism is calculated by finding the product of 5/2, the prism's apothem length, the side of its base and its height.** The formula is given as V = 5/2 abh, where "V" denotes the volume, "a" indicates the apothem length, "b" represents the side and "h" is the prism's height.

The volume of a simple prism is calculated by multiplying its area by its height. A prism is a three-dimensional geometric figure that contains plain sides, identical bases and uniform cross-sections along its length. A pentagonal prism has five rectangular surfaces and two pentagonal bases, which are parallel. Other types of prisms include triangular prisms and hexagonal prisms.