67% of teenagers, ages fifteen to seventeen, are concerned about their credit scores. Suppose we randomly select fifteen- to seventeen-year-old teenagers until we find one who is concerned about his/her credit score. Let X be the number of teenagers we select who are not concerned about their credit scores before we find the first teenager who is concerned . Let Y be the number of teenagers we select who are not concerned about their credit scores before the second teenager who is concerned is found. a. What is the probability that none of the first three people are concerned about their credit scores? b. What is the expected value of X? c. What is the variance of X? d. What is the probability that X = 0? e. What is the probability that X 4? f. What is the probability that Y = 6? g. What is the probability that Y = 0?