1) In a study entitled How Undergraduate Students Use Credit Cards, Sallie Mae reported that undergraduate students have a mean credit card balance of . This figure was an all-time high and had increased over the previous five years. Assume that a current study is being conducted to determine if it can be concluded that the mean credit card balance for undergraduate students has continued to increase compared to the April report. Based on previous studies, use a population standard deviation=1000 .

a) What is the p value for a sample of 160 undergraduate students with a sample mean credit card balance of 3639? If your answer is zero enter "0".

z value=

p value=

2) On its municipal website, the city of Tulsa states that the rate it charges per5 CCF of residential water is$21.62 . How do the residential water rates of other U.S. public utilities compare to Tulsa's rate? The fileResidentialWatercontains the rate per5 CCF of residential water for42 randomly selected U.S. cities.

null hypothesis: H0: u=21.62

a)What is thep value for your hypothesis test? Round your answer to four decimal places.

b) Repeat the preceding hypothesis test using the critical value approach.

The critical value(s) is(are) +/- 2.02

t=