Use of Texting. TextRequest reports that adults 18-24 years old send and receive 128 texts every day. Suppose we take a sample of 25-34 year olds to see if their mean number of daily texts differs...

Use of Texting. TextRequest reports that adults 18-24 years old send and
receive 128 texts every day. Suppose we take a sample of 25-34 year olds
to see if their mean number of daily texts differs from the mean for 18-
24 year olds reported by TextRequest.

a. State the null and alternative hypotheses we should use to test
whether the population mean daily number of texts for 25-34 year
olds differs from the population daily mean number of texts for 18-
24 year olds.
b. Suppose a sample of thirty 25-34 year olds showed a sample mean of 118.6 texts per day. Assume a population standard
deviation of 33.17 texts per day and compute the p-value.
c. With a = .05 as the level of significance, what is your conclusion?
d. Repeat the preceding hypothesis test using the critical value
approach.