5. The figure below shows the temperature during a day in Ames. (a) What was the average change in temperature from 9 a.m. to 1 p.m.?

5. The figure below shows the temperature during a day in Ames.

(a) What was the average change in temperature from 9 a.m. to 1 p.m.?

(b) Estimate how fast the temperature was rising at 10 a.m. and at 7 p.m.