11.1 The Supply Function for the Output of an Activity (or for an Individual Product)11.2 The Demand Function for a Variable Input11.3 The Marginal (Net) Revenue Productivity Function for an Input11.4 The Marginal Cost Function for an Activity (or Individual Product)11.5 Minimizing the Cost of Producing a Given Output11.6 Determination of Marginal Productivity, Average Productivity, Marginal Cost, and Average Cost Functions