Zess Zess's Fabrication has the following aggregate demand requirements and other data for the upcoming four quarters. Quarter Demand quarter's 1300 units Previous output 1 1800 Beginning inventory 0 units 2 1100 Stockout cost $150 per unit 3 Inventory holding cost $40 per unit at end of quarter Hiring workers $40 per unit Firing workers $80 per unit Subcontracting cost $60 per unit 11:4 t 00 4 1600 900