Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the night shift than on the day shift. The mean number of units produced by a sample of 54 day-shift workers was 345. The mean number of units produced by a sample of 60 night-shift workers was 351. Assume the population standard deviation of the number of units produced on the day shift is 21 and 28 on the night shift. Using the .05 significance level, is the number of units produced on the night shift larger?

a. State the null and alternate hypotheses.

b. Compute the test statistic.

c. Compute the p-value.

d. What is your decision regarding the null hypothesis?

e. Interpret the result.