The U.S. Department of Transportation regularly publishes the Air Travel Consumer Report, which provides a variety of performance measures of major U.S. commercial airlines. One dimension of performance reported is each airline’s percentage of domestic flights arriving within 15 minutes of the scheduled arrival time at major reporting airports throughout the country. Use these data, given in the file P2_12.XLS, to answer the following questions:

a. Which major U.S. airline has the highest third quartile on-time arrival percentage?

b. Which major U.S. airline has the lowest first quartile on-time arrival percentage?

c. Which major U.S. airline has the largest range of on-time arrival percentages?

d. Which major U.S. airline has the smallest range of on-time arrival percentages?