Firing a piece of pottery in a kiln takes place at different temperatures for different amounts of time. The graph below shows the temperatures in a kiln while firing a piece of pottery after the kiln is preheated to 200ºF. Connor, Greg, and Amaya have been arguing about which time interval the temperature in the kiln showed the greatest average rate of change.

Connor says the greatest rate of change occurred from 5 hours to 8 hours.
Greg says the greatest rate of change occurred from 1 hour to 1.5 hours.
Amaya says the greatest rate of change occurred from 0 to 1 hour.

Who is correct? Justify your choice