Flight operation ( salaries of flight crew), fuel, maintenance, airport operations (salaries of ground crew), passenger services (meal, baggage), marketing and advertising, sale and reservations, general and administrative, depreciation in some case as follow:

1. A company want to add a new flight to an existing route, and it believe it can re-arrange its staff such that it would not need to add any new personnel.
2. Adding four or more flights to existing routes, it will have to add two pilots and flight attendants.
3. Add a new route, it will also have to add a ground crew and maintenance staff. Could you have me to figure out?