How many miles can a Toyota Corolla S run until its empty?

I just got a new car for a graduation gift and its a 2005 Toyota Corolla S. I bought it at a used car lot and it was a trade in. There was no manual that came with the car and im planning on taking a trip. So im hoping someone else has the same car and they can tell me exactly how many miles to the gallon the car gets. Thanks! :)