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Introduction to Calculus in Economics: Calculus is a powerful tool used in economics. One of the initial applications areas is the study of a firm, a topic in microeconomics. An important function is the cost function function C (I), the cost of producing z items (of whatever they are selling). This question deals with just the cost function C (I). Problem Set question: The cost, in dollars, of producing a units of a certain item is given by C(z) = 15r - 10VI - 8. Find the production level that minimizes the average cost per unit. The number of units that minimizes the average cost is Number T