Jacob Lee is a frequent traveler between Los Angeles and San Diego. For the past month, he wrote down the flight times in minutes on three different airlines. The results are:

Goust Jet Red Cloudtran
51 50 52
51 53 55
52 52 60
42 62 64
51 53 61
57 49 49
47 50 49
47 49
50 58
60 54
54 51
49 49
48 49
48 50

a. Use the 0.05 significance level and the five-step hypothesis-testing process to check if there is a difference in the mean flight times among the three airlines.
b. Develop a 95 percent confidence interval for the difference in the means between Goust and Cloudtran.