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.