10.

Aggregate Planning: Given the following cost information and the aggregate plan below:

Quarter	Demand		Previous production level	500	units
1	800		Inventory holding cost	$9	per unit
2	900		Hiring workers	$43	per unit
3	1000		Laying off workers	$91	per unit
4	700		Subcontracting cost	$120	per unit
			Regular time production cost	$91	per unit

Quarter	Demand	Regular time production	Ending Inventory	Subcontract	Hiring	Laying Off
0		500	0
1	800	800	0		300	0
2	1000	1000	0		200	0
3	400	400	0		0	600
4	500	500	0		100	0

Calculate the overall cost for quarters 1 to 4. Do not include the regular time production cost from quarter 0 and the cost of the inventory from quarter 0.