Cooper's hierarchy of costs is based on allocation by activity rather than volume.

a. Unit-level costs are like variable costs; they are constant per unit but change in total with the number of units produced.

b. Batch-level costs are like fixed costs; they vary per unit but are constant in total.

These costs recognize economies of scale.

c. Product-level costs are incurred in manufacturing a product or product family.

d. Facility-level costs are not related to a particular unit or batch or family of products; they are necessary to sustain a company's overall operations.