The success of an airline depends heavily on its ability to provide a pleasant customer experience. One dimension of customer service on which airlines compete is on-time arrival. The file LateFlights contains a sample of data from delayed flights showing the number of minutes each delayed flight was late for two different airlines, Delta and Southwest.

Company Delta
34 59 43 30 3
32 42 85 30 48
110 50 10 26 70
52 83 78 27 70
27 90 38 52 76
Company Southwest
46 65 41 34 67
106 45 28 39 86
74 46 33 51 63
43 34 32 64 65

(a) Formulate the hypotheses that can be used to test for a difference between the population mean minutes late for delayed flights by these two airlines. (Let μ1 = population mean minutes late for delayed Company Delta flights and μ2 = population mean minutes late for delayed Company Southwest flights.)

a) H0: μ1 − μ2 ≤ 0;
Ha: μ1 − μ2 > 0
b) H0: μ1 − μ2 ≥ 0;
Ha: μ1 − μ2 < 0
c) H0: μ1 − μ2 = 0;
Ha: μ1 − μ2 ≠ 0
d) H0: μ1 − μ2 ≠ 0;
Ha: μ1 − μ2 = 0
e) H0: μ1 − μ2 < 0;
Ha: μ1 − μ2 = 0

(b) What is the sample mean number of minutes late for delayed flights for each of these two airlines?
(c) Calculate the test statistic. What is the p-value?
(Round your answer to four decimal places.)