The following lots of a Commodity P were available for sale during the year.

Beginning inventory	5 units at $61
First purchase	15 units at $63
Second purchase	10 units at $74
Third purchase	10 units at $77

The firm uses the periodic system, and there are 20 units of the commodity on hand at the end of the year.

What is the amount of cost of goods sold for the year according to the average cost method?

a.$1,380

b.$1,250

c.$1,510

d.$1,375