A monopolistically competitive firm faces the above demand schedule for its product. The firm has total fixed costs of $9 and a constant marginal...

A monopolistically competitive firm faces the above demand schedule for its product. The firm has total fixed costs of $9 and a constant marginal cost of $3 per unit. The firm will maximize profit with

30 units of output.

15 units of output.

21 units of output.

16 units of output.

9 units of output.