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5. Continuing the last question, which of the following is closest to the variance ofX?(a) 1(b) 3.75(c) 7.5(d) 10(e) 156. Suppose that in one area in California, 40% of all homeowners are insured against earthquakedamage. Four homeowners are to be selected at random; letXdenote the number amongthe four who have earthquake insurance. What is the distribution ofX?7. Continuing the last question, what is the probability thatX≥2?8. Suppose an operator receives phone calls according to a Poisson process, at a rate of 36 callsper hour. LetXbe the number of calls that arrive within a 5-minute period. What is thevariance ofX?9. A family decides to have children until it has three girls. Assume that different births areindependent withP(boy) =P(girl) = 0.5. LetXbe thetotalnumber of children the familywill have eventually. What is the expected value ofX?(a) 3(b) 4.125(c) 5(d) 6(e) none of the above2