The New York City Department of City Planning (2006) studied pedestrian walking speeds. The report stated that pedestrians who were en route to work walked a median of 4.41 feet per second, whereas tourist pedestrians walked a median of 3.79 feet per second. They did not report results of any hypothesis tests. 

a. Why would an independent-samples t test be appropriate in this situation? 

b. What would the null hypothesis and research hypothesis be in this situation?