I am having trouble solving the question with the given data. Please explain step by step.

DATA

Quantity of Labor Total Output Fixed Cost Variable Cost

0 0 $160

1 16 $80

2 40 $160

3 60 $240

4 72 $320

5 80 $400

6 84 $480

QUESTION

What is the Marginal Cost (MC) for the 40th unit of output?

Select one:

a. 3.30 - correct

b. 0

c. 5

d. -5