2. (11 points} Suppose we want to do a poll to see what is the percentage, p of voters that will support president candidate A over candidate B. Assume that whether a person will vote for candidate A over candidate B is a Bernoulli trial, and the chance of a person voting for either candidate is equal. a) How many people do you need to poll so that the percentage p is within 2% 'om its true value with 9% condence? [Hint The percentage p is the mean of the random variables which represent a vote for candidate A over candidate B, and use central limit theorem.] b) It'you poll 41313 people, how many must prefer candidate A to B so that the 90% condence interval is entirely above p=