Final answer:
The units of f'(x) are dollars per sheet of paper.
Step-by-step explanation:
The units of f'(x) in this context would be dollars per sheet of paper.
f(x) represents the cost of producing a certain number of sheets of paper, which is measured in dollars. Taking the derivative, f'(x), would give us the rate of change of the cost with respect to the number of sheets produced, which is the cost per sheet of paper.