An individual has $ 100 initially. He repeatedly plays a game of chance in which he earns $ 100 with probability 0.8 or loses $ 100 with probability 0.2. The stops playing at the first of two possibilities: he has no more money or he has 400$.
(A) On average, how many times will heplays?
(B) What is the probability that he will end with $ 400?
(C) Calculate the expected profit. Would he have had a better expected profit if he started with $ 200?