It's hard for me to digest in steps. I'm not exactly a math person. :P
For A) would it be...
13C5
Would that make sense at all?
For B...
To choose 3 of a kind from 4 cards... it would be 4 choose 3? That would equal 4 ways... For the pair, if you took 3 cards from the original deck...
1. In Poker:
A) A flush is 5 cards of the same suit not in any order. How many flushes are possible?
B) A full house is 3 of a kind plus a pair. How many full houses are possible?
2. n C r (That's all I can think of right now)
3. For A)
(13 C 5) / (52 C 5) = 33 / 66640...