This table displays the height of a balloon as it floats away.



A 2-column table with 6 rows. Column 1 is labeled Time (minutes) with entries 10, 11, 12, 13, 14, 15. Column 2 is labeled Height (feet) with entries 64, 73.5, 83, 92.5, 102, 111.5.



What is the rate of change for the height as the time increases by 1 minute?





Rate of change =