Variables Inventory carrying cost Subcontracting cost Average pay rate Overtime pay rate Labor-hours needed to produce one unit Units per day produced Cost $7 per unit per month $25 per unit $12 per hour (8 hours per day) $18 per hour (above 8 hours per day) 1.5 hours per unit Beginning inventory Planned ending inventory Lost sales per unit 50 0 0 $30 This chart provides the demand for the product and the number of production days per month. Months January February March April May June Demand 1300 800 600 Production Days 22 18 21 1500 1300 21 22 1300 20