15. Let C(q) and R(q) represent the cost and revenue, in dollars, of making q tons of paper. = = (a) If C(10) = 30 and C'(10) = 7, estimate C(12). (b) Assuming C(10) > 0, is the estimate from part (a) above or below the actual cost? (c) If C'(40) = 8 and R'(40) = 12.5, approximately how much profit is earned by the 41st ton of paper? (d) If C'(100) = 10 and R'(100) = 11.5, should the company make the 101st ton of paper? Why or why not? = =