One, but they'll take 30 visits to do it.
Have you tried turning it off and back on?
Just two, but more can join in if there's room in the lightbulb.
Technically, just two, but it is really hard to get them to breed in captivity.
One
Interviewer:"If the Earth rotates 30 times faster, what will happen?" engineer:"We will get our salary everyday" :D Think Greedily Act Confidently
asked every guy under 30.
Because he didn't know what alignment. I hope this one cracks you up!