Here is my question.

Problem 13: A bank puts together an ad campaign to encourage its clients to use its credit card. The before and after stats (for a month) for 9 randomly selected clients are: Client 1 2 3 4 5 6 7 8 CO Before 10 17 8 36 24 14 19 5 21 After 15 14 13 42 20 12 25 9 22 Difference 5 -3 5 6 -4 -2 6 4 1 Was the ad campaign successful based on this random sample? Use the T-Distribution with a 95% level of confidence (data is 5% significant) and then an 80% level of confidence (data is 20% significant). Note the importance of the alpha (5% and 20%)