Pavarti's Sandwiches Sells Its Signature 2-Foot Long Sub Sandwiches

Pavarti's Sandwiches sells its signature 2-foot long sub sandwiches. These sandwiches are so good, it is the only item on the menu. In recent years, Pavarti's breakeven point has been 30,000 sandwiches. Annual fixed cost are $600,000 and the sandwiches have a sales price of $27.
What is the contribution margin per unit of each sandwich?

A) $7
B) $15
C) $20
D) $27
E) None of the above