The 99 percent confidence interval for the population mean is found from:


The answer is:
9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99, 108
The 6th term is 108
Property of zero as an exponent
6.5 because you instantly take $9.50 away from $55. After you get that answer, you will have 45.5. Then divide 45.5 by 7 which will give you 6 and a half hours.