Can you replace the question mark with a number?

If vegetarians eat vegetables, what do humanitarians eat?
Don`t think that you`re thinking. If you think that you're thinking you only think that you're thinking.
When I erase a word with a pencil, where does it go?
If a train station is where a train stops, what is a workstation?
Why is it, when a door is open it's ajar, but when a jar is open, it's not adoor?
Ever wonder what you call a pocket calculator in a n*dist camp?
If you jogged backward . . .would you gain weight?
Being rich and it don't mean so much . Just look at Henry Ford, all those millions and he never owned a Cadillac!
Why do they put pictures of criminals up in the Post Office? What are we supposed to do . . . write to these men? Why don't they just put their pictures on the postage stamps so the mailmen could look for them while they delivered the mail?
Employment application blanks always ask who is to be notified in case of an emergency. Wouldnt a good response be to write . . . A Good Doctor!