Request for help on probability.

Hi All,
I need your help to solve this question. I am preparing for exam and trying to solve this question.

A ball is selected from a box containing 2 black balls, numbered 1 and 2, and 2 white balls, numbered 3 and 4. The number and color of the ball is noted, so the sample is {(1,b), (2,b), (3,w),(4,w)}.
Assuming that four outcomes are equally likely, find P[A|B] and P[A|C], where A, B and C are following events:
A= {(1,b), (2,b)}, "black ball selected",
B= {(2,b), (4,w)}, "even-numbered ball selected" and
C= {(3,w), (4,w)}, "number of ball is greater than 2".