Given the cost function of producing x items is C(x) = 15x + 1000 and the revenue function of selling these x items is R(x) = 30x², both in dollars, find: a) The profit function. b) The marginal cost, marginal revenue and marginal profit functions. c) Evaluate all the functions you found in part b) at x = 100 and interpret the answers.

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The cost of producing x textbooks is given by C(x)= 1200+40x.  If textbooks are sold for $60 dollars determine the following: a) the fixed costs b) the revenue function c) the number of textbooks that need to be sold to break even.

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