Eagle Fabrication has the following aggregate demand requirements and other data for the upcoming four quarters.

Quarter	Demand		Previous quarter's output	1500 units
1	1300		Beginning inventory	200 units
2	1400		Stock-out cost	$50 per unit
3	1500		Inventory holding cost	$10 per unit at end of quarter
4	1300		Hiring workers	$4 per unit
			Laying off workers	$8 per unit
			Unit cost	$30 per unit
			Overtime	$10 extra per unit

What is the cost of the following plans:

a. Plan Achase demand by hiring and layoffs.

b. Plan Bproduce at a constant rate of 1200 and obtain the remainder from overtime.

c. What plan would you choose?

please also explain why the ending inventory for plan B is 100?