Suppose that the cost of producing $\small {x}$ sheets of paper is $\small{C = f(x)}$ dollars.

(a) What are the units of $\small{f\;'(x)}$? (Write each word in its entirety, in lower case).

Units: /

(b) If you've already produced 1710 sheets, estimate the cost of producing an additional sheet if $\small{f\;'(1710) = 1400}$.

Cost:

Your overall score for this problem is