Question: a) The manager of the credit department for an oil company would like to determine whether the average monthly balance of credit card holders is greater than $75. An auditor selects a random sample of 100 accounts and finds that the average owed is $83.40. The population standard deviation is known to be $32.65. Using the 0.05 level of significance, should the auditor conclude that there is evidence that the average balance is greater than $75?

b) Also calculate the p-value.