Use this information to answer the questions that follow.

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

Beginning inventory

First purchase

Second purchase

Third purchase

$5$ units at $$61$

$15$ units at $$63$

$10$ units at $$74$

$10$ units at $$77$

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

What is the cost of goods sold for the year using the weighted average cost method?

a$.$ $$1,375$

b$.$ $$1,510$

c$.$ $$1,380$

d$.$ $$1,250$