10. All of the information required in the computation of cost of goods sold is presented below, except for purchases, which must be what amount?

Purchase discounts	$ 300
Inventory, December 31	2,500
Cost of goods sold	9,500
Purchases	?
Inventory, January 1	1,500
Freight-in	500

a.	$ 9,600
b.	$10,300
c.	$11,100
d.	$10,200