(10 points total) A savings and loan association needs information concerning the checking account balances of its local customers. A random sample of 14 accounts was checked and yielded a mean balance of $664.14 and a standard deviation of $297.29. Find the following.

a.Assuming that these 14 accounts can be considered a random sample,construct a 95% confidence intervalfor the true mean checking account balance for local customers. (Assume that the normal probability plot doesn't exhibit major departure from the normality assumption.) (6 points)

b.Interpretin words as it pertains to this situation the confidence interval found in part a). (2 points)

c.If you lower theconfidence level to 90%would you get a more precise estimate or a less precise estimate?Explain. (2 points)