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Question 7 9.6 pts Suppose we have the following PDF for a random variable x f(z) = 12, 15:53 elsewhere If we know E(X) = !" find Var(3X -2). 0 11/4 o None of these 0 51/2 . 11/12 0 0 Question 8 9.54 pts In Star Wars, an Empire stormtrooper averages 3 hits on rebel scum per battle (they have terrible aim). What is the probability that a stormtrooper had between 4 and 5 hits in the two battles at the Death Stars? o None of these Question 9 9.54 pts The probability that a patient suffering from spontaneous pneumothorax (sudden collapsed lung) will require a corrective surgery is 0.6, what is the probability that 3 to 10 of the next 15 patients will require the surgery? 0.7824 0.7808 . None of these 0.5965 0.5949 Question 10 9.54 pts The probability that a mouse has a particular genetic anomaly of medical interest is 0.1, what is the probability we must examine 15 mice to obtain exactly 8 that have the genetic anomaly? . (15) (15 ) O E 1.5.81 . (2) (.1) (.9)7 o None of these . (7) (.1)8(9)7