Beginning inventory @ May $1$

First purchase @ May $7$

Second purchase @ May $17$

Third purchase @ May $23$

Sales@ May $31$

$2,100$ units @$$5\mathrm{.}80$

$2,200$ units @$$6\mathrm{.}00$

$2,400$ units @$$6\mathrm{.}10$

$2,000$ units @$$6\mathrm{.}20$

$6,600$ units@ $$7\mathrm{.}70$

What is the amount of cost of goods sold assuming the LIFO cost flow method?

Multiple Choice

$$39,600$

$$40,920$

$$38,280$

$$40,240$