Answer:
$7
Explanation:
Given: Sales volume= 1000 units.
      Sales= $20000.
      Variable expense= $13000.
      Contribution margin= $7000.
      Fixed expense= $3780
      Net operating income= $3220.
Now, finding the contribution margin per unit.
Formula; Contribution margin per unit= [tex]\frac{(sales- variable\ expense)}{Number\ of\ sales\ units}[/tex]
⇒ Contribution margin per unit=  [tex]\frac{(20000-13000)}{1000}[/tex]
⇒ Contribution margin per unit= [tex]\frac{7000}{1000}[/tex]
∴ Contribution margin per unit= [tex]\$ 7[/tex]
Hence, $7 is the contribution margin per unit.