2. UA Cinema wants to know what proportion of its customers is under age 21. A random bsample of 500 customers was taken, and 375 of them were found under age 21. Assume that the population proportion of customers under age 21 is 0.68.
(a) What is the probability that the sample proportion is within 0.3 of the proportion of customers who is under age 21?
(b) Assumer that the population proportion is unknown. Find the 95% confidence interval for the proportion of customer who is under age 21.