14. Angels Beauty Box specializes in curling cream for natural hair. The following data was gathered for the last three years.

	Total cost of production	Volume
Year 1	13500	700
Year 2	15,100	900
Year 3	18,300	1100

What is the best estimate of the company's variable cost per unit for the period?

a.

$20

b.

$4

c.

$17

d.

$12