15. Suppose now that events A, B and C are pairwise mutually independent with P(A)=0.3, P(B)= 0.4, P(C)=0.5. Compute the following: (i) P(An BnC), (ii) P(ABC), () P(ABC). 16. There are 4 black balls, and 4 white ones in an urn. You pick 4 balls. (a) Compute the probability distribution function of Y, the number of black balls you get. (b) You win 2 per black ball you get, and an extra 20 if you get all 4 black balls. What is your expected gain?