A doctor asked his lawyer friend.

The Doctor: I want to ask you a legal question.

The Lawyer: What is it?

The Doctor: Can I charge for a medical advice?

The Lawyer: Of course. You can charge up to $100.

The Doctor: OK. You owe me $100 for the medical advice you asked me last week.

The Lawyer: No Problem, but guess how much I charge for a legal advice? you guessed it…$100. That makes us even.