Use the following information to answer questions 50-52.
Skyline Tours is offering hot-air-balloon tours. The tables below give information about the balloon, the equipment, and the tours offered.
52. Jarrod went on Tour A, and his trip covered a distance of 6 miles. Bhumi went on Tour C, and her trip covered a distance of 9 miles. Which of the following values is the difference, in miles per hour, of the average speeds of their balloons during their tours?