Hammerhead Charters runs fishing trips out of the local port. Hammerhead charges $80 per trip for a half-day trip. Variable costs for Hammerhead total $35 per trip and the fixed costs are $10,350 per month. Hammerhead is subject to an income tax rate of 20 percent.

Required:

a. How many trips must Hammerhead sell to break even?

b. How many trips must Hammerhead sell to earn a monthly operating profit of $10,800 after taxes?