A very Common situation in holdem question.

[Komodo]

Were in a holdem game and hold A [img]/images/graemlins/heart.gif[/img] and K [img]/images/graemlins/club.gif[/img].

Flop comes K [img]/images/graemlins/heart.gif[/img] 2 [img]/images/graemlins/spade.gif[/img] and 2 [img]/images/graemlins/club.gif[/img]
The players are pretty loose, so we can assume they play random cards or almost random cards.
How big is the probability that another player is holding a 2?
Heads-up?
Against 2 other players
Against 3 other?
Against 4?
Against 5?
Against 6?
Agaisnt 7?
Against 8?
Against whole table?