If you were a taxi driver, the daily revenue and costs are as the following:

Revenue: $240

Variable costs (gas, your labor...): $180

Mortgage payment for car: $50

License Fee: $40

For profit-maximization, will you operate your taxi business today? What is the minimum daily revenue to keep the operation in the short-run? What is the minimum daily revenue to keep the operation in the long-run? Please show the calculation.