Answer:
The answer is: 2) operate his business as long as he rents at least 1 boat per month.
Step-by-step explanation:
Since Bill doesn't have any fixed costs, then he should continue to work as long as he can rent at least 1 boat per month. The break even point is calculated by dividing the total fixed costs over contribution margin per unit, but since the total fixed costs equal 0, then any boat rented will be over the break even point.