Six. Why? It just does! OKAY!
You don't need to, they glow in the dark.
Three. One to do it, one to complain that it has already been done before, and one to repost this joke.
They both need to be changed after a while for the same reason
1001 1 to offer up the bulb and 1000 to scream 'Get in the hole'
You can negotiate with a terrorist.
Mad Cow disease was already taken.