in a las vegas casino, gamblers lose a mean of 0.10 on each roulette game, with a standard deviation of 3.47. (since the standard deviation is quite high with respect to the mean, roulette players often win money on a bet.) suppose a gambler plays roulette for 250 bets straight. what is the probability that he will be winning after 250 bets? (hint: he is winning when the amount of his total earnings is positive.)