A bank with branches located in a commercial district of a city and in a residential area has the business objective of developing an improved process for serving customers during thenoon-to-1 P.M. lunch period. Management decides to first study the waiting time in the current process. The waiting time is defined as the number of minutes that elapses from when the customer enters the line until he or she reaches the teller window. Data are collected from a random sample of 15 customers at each branch. Complete parts(a) through(d) below.

a. Assuming that the population variances from both banks areequal, is there evidence of a difference in the mean waiting time between the twobranches? (Use =0.05.)

Let 1 be the mean waiting time of the commercial district branch and 2 be the mean waiting time of the residential area branch. Determine the hypotheses. Choose the correct answer below.

Find the test statistic. (Round to two decimal places asneeded.)

Find the criticalvalue(s). (Use a comma to separate answers as needed. Round to two decimal places asneeded.)

Choose the correct conclusion below.

A.Donotreject H0. There is insufficient evidence that the mean waiting time between the two branches differ.

B.Reject H0. There is insufficient evidence that the mean waiting time between the two branches differ.

C.Donotreject H0. There is sufficient evidence that the mean waiting time between the two branches differ.

D.Reject H0. There is sufficient evidence that the mean waiting time between the two branches differ.

b. Determine thep-value in(a) and interpret its meaning.

p-value= (Round to three decimal places asneeded.)

Interpret thep-value. Choose the correct answer below.

A. It is the probability of obtaining a sample that yields at-test statistic farther away from 0 in the positive direction than the computed test statistic if there is no difference in the mean waiting time between commercial and residential banks.

B .It is the probability of obtaining a sample that yields at-test statistic farther away from 0 in either direction than the computed test statistic if there is no difference in the mean waiting time between commercial and residential banks.

C. It is the probability of obtaining a sample that yields at-test statistic farther away from 0 in the negative direction than the computed test statistic if there is no difference in the mean waiting time between commercial and residential banks.

D. It is the probability the two banks have different population mean waiting times.

c. In addition to equalvariances, what other assumption is necessary in(a)?

A. Both sampled populations are not approximately normal.

B. The samples are specifically chosen and not independently sampled.

C. Both sampled populations are approximately normal.

D. The sample sizes must be equal.

d. Construct and interpret a 95% confidence interval estimate of the difference between the population means between the two branches.

The 95% confidence interval is (Round to three decimal places asneeded.

Interpret the confidence interval. Choose the correct answer below.

A. With 5% confidence, the difference between the population mean waiting time between the two banks falls above the upper confidence interval limit.

B. With 5% confidence, the difference between the population mean waiting time between the two banks falls below the lower confidence interval limit.

C. With 95% confidence, the difference between the population mean waiting time between the two banks falls outside this interval.

D. With 95% confidence, the difference between the population mean waiting time between the two banks falls in this interval.