Nun.
At least two, but they have to be pretty small to fit.
Two. One to hold it in place, another to rotate the universe around it.
None, it's a hardware problem!
You never can tell. The Sandpeople always ride in single file to hide their numbers.
He finishes her drink EDIT: Apparently this is Conan's joke, so all credit goes to him. I just heard it from a friend of mine and I had no idea.
Screw it. EDIT: has a better answer
Customer: "Rectangular 15x11 centimeters."