Do people walk faster in the airport when they are departing or when they are arriving? Researchers measured the walking speed of 51 departing travelers and 71 arriving travelers at Sacramento International Airport. They found that departing travelers had a mean walking speed of 260 ft/min, and arriving travelers had a mean walking speed of 248 ft/min. The standard deviation was 37 ft/min for departing travelers and 56 ft/min for arriving travelers. a. Construct a 81% confidence interval for the difference in mean walking speed between departing and arriving travelers. Critical value: A or t * = (Enter the positive one.) Margin of Error: E = C] Condence Interval: ([:], [:]) b. Interpret your result in part (a) in a complete sentence. c. Based on your condence interval, can you conclude that departing travelers walk at a different speed than arriving travlers? OYes O No