A box contains 15 - K red balls, 5 + K green balls and 7 blue balls. Three balls are drawn without replacement. Let A, B and C be events defined as follows: . Event A: at least one blue balls is drawn. Event B: the second ball drawn is green. Event C: one ball of each colour is drawn. (a) Find the probabilities P(A), P(B) and P(C) respectively. (b) Find P(B n C). (c) What is the probability that Event B will occur given that Event C has occurred