9. Suppose the systolic blood pressure of young adults is nor. mally distributed with mean 121] and standard deviation 11. {a} Find the TTth percentile of this distribution. [b] Find the probability that a random young adult has sys tolic blood pressure above 135-. {c} Find the probability that a random young adult has sys tolic blood pressure within 3.3 stande deviations of the mean. [d] Suppose you take a sample of 8 young adults and measure their average systolic blood pressure. Find the probabil' ity that the average blood pressure is between 115 and 123. 1|]. Suppose that. in the next federal election. 4% of votes vvill be for the Liberal Party. TAlt-"l'lat is the probability that more than 430 votes in a sample of mill will be for the Lib- eral Party? Use a normal approximation. but rst verify that it is valid to do so