The current aggregate demand requirements for a firm are shown below for the next six months:May demand $120$June demand $100$July demand $100$Aug demand $100$Sep demand $130$Oct demand $150$The firm always plans to meet all demand. The firm currently has $120$ workers capable of producing $120$ units in a month $(1$ unit$/$worker$).$ The workforce can be increased $($at a cost of $$500$ per worker$)$ or decreased $($at a cost of $$1,000$ per worker$).$ Inventory holding cost is $$100$ per unit per month. The firm currently has $40$ units of inventory on hand, and it would like to have $40$ units available at the end of each month. Regular production cost is $$3,000$ per unit.a$.$ What should the aggregate plan be if the inventory holding cost is to be minimized?b$.$ What is the cost of this plan?a$.$ The aggregate plan should be to decrease the workforce to match the required $77$ workers.b$.$ The cost of this plan is the total cost calculated in Step $9$