General Motors has provided the following information:

	Cost per Unit		Cost per Period
Direct materials	$	7.05
Direct labor	$	3.50
Variable manufacturing overhead	$	1.65
Fixed manufacturing overhead			$	11,000
Sales commissions	$	1.00
Variable administrative expense	$	0.40
Fixed selling and administrative expense			$	5,500

If the selling price is $18.70 per unit, the contribution margin per unit sold is closest to:

Select one:

a. $1.80

b. $4.30

c. $5.10

d. $8.15