3, and the rest are true stories.
1, 2, 3, 95, 98, ME, NT, 2000, XP, Vista, 7, 8, 10.
The mathematician says "2" The Physicist says "2, plus or minus 0.1" The engineer says "Probably around 2, but let's say 3 to be on the safe side".
A certain number! One to actually perform the task, and the rest to act in a manner stereotypical of the group.
Rest in pieces.
Lawyers don't think they're funny, and nobody else thinks they're jokes.
One... The rest are true stories.