2. If a person’s temperature after x hours of strenuous exercise is T (x ) = x 3 (4 − x 2 ) + 98.6 degrees Fahrenheit (for 0 ≤ x ≤ 2 ), find the rate of change of the temperature after 1 hour.

3. Based on a recent study, the “happiness” of people who live in a country whose average temperature is t degrees Fahrenheit is given by h(t ) = 8.2 − (0.01t − 2.8) 2 , for 35 ≤ t ≤ 72 (“Happiness” was rated from 1 = “not at all happy” to 4 “very happy”.) Find h (40) and h ' (40) . Interpret your answer.