Thequality-control manager at a compact fluorescent light bulb (CFL) factory needsto determine whether the mean life of a large shipment of CFLs is equal to7,500 hours. The population standard deviation is 1,000 hours. A random sampleof 64 CFLs indicate a sample life of 7,250.

a. State the Null andAlternative Hypothesis.

b. Draw the normal curveand show the Acceptance and Rejection Areas, using 0.05 level of significance

c. At the 0.05 level ofsignificance, is there evidence that mean life is different from 7,500 hours. Show all steps. ( seepages 278-279)

d. Compute the p-value andinterpret its meaning. Show all steps

e. Construct a 95%confidence interval estimate of the population mean life of the CFLs. Show allsteps.

f. Compare the results of(c) and (e). What conclusions do you reach?