Use this inventory information for the month of March to answer the following question.

March	1		Beginning inventory	30 units @ $56
	7		Purchase	60 units @ $60
	18		Sale	25 units
	22		Purchase	10 units @ $66
	29		Sale	40 units

Assuming that a periodic inventory system is used, what is cost of goods sold on a FIFO basis?

a. $3,780

b. $3,861

c. $2,160

d. $5,940