This shouldn't be that hard of a question, but I'll ask anyway and look like an idiot... it's late and I'm tired.
A) Let's say you have 22 in the BB and 3 people are in the pot. Make the assumption that anyone in the pot for sure doesn't have a 2 (although someone that folded may or may not have had a 2). Do your odds for flopping a set go up? I'm thinking they would go up to 2/44 + 2/43 + 2/42 = 13.96% instead of 12.25% if nothing was taken into consideration. I just can't convince myself that this is true/false
B) Would a more accurate way to calculate the odds of flopping a set take into account the odds of both 2's being dealt preflop * 0 + odds of one 2 being dealt preflop * x% + odds of no 2s being dealt preflop * y%? Is this at all different than the 12.25% or just a more complicated way to calculate the same number?