1. GreenGrass is a manufacturer of lawnmowers. GreenGrass needs 40 pounds of aluminum to manufacture one lawnmower, and there is maximum 2,000 pounds available per month (you cannot store more). The manufacturing cost is $1,200 per unit during the first month, and $1,500 during the second month. Your cost of holding 1 lawnmower in inventory is estimated at $100 per month. You have to meet a demand of 30 lawnmowers in month 1, and 60 lawnmowers in month 2. In addition, GreenGrass plant manager wants to produce at least 20 units per month. GreenGrass would like to minimize its total cost while meeting demand.

Formulate this problem as a linear program. By following the 4 steps, write out the linear model.