2. Get ready Analyze the monthly sales of shirts, including t-shirts and polo shirts, shown in Figure 5-17 (duplicated below). Identify the decision variables, constants, and output variables. 3. Now you try it In the following space, answer these questions: What are the constants, decision variables, and output variables? How much money can Lawrence Media make per month from the sales of shirts? Which type of shirt should they promote the most aggressively