Exercise 4 You are shopping around for a pair of concert tickets on StubHub, and you collect a random sample of 17 prices for the pair of tickets. Using this random sample, StubI-lub calculates that a 70% confidence interval for the true mean price is given by [$65, $88]. Assume the ticket prices follow a Normal distribution. [a] Calculate f, the sample mean. [b] Calculate s, the sample standard deviation. [c] Construct a 90% condence interval for pt. Interpret the condence interval within the context of the exercise