A cricket makes a chirping noise by sliding its wings together rapidly. Perhaps you have noticed that the number of chirps seems to increase with the temperature. The following data list the temperature (in degrees Fahrenheit) and the number of chirps per second for the striped ground cricket.

Temperature, x ………………………. Chirps per Second, C

30…………………………………………………….. 13.3

40 …………………………………………………….. 11.6

50 …………………………………………………….. 10.9

60 …………………………………………………….. 13.7

 70 ………………………………………………………. 22.3

80 …………………………………………………….. 30.2

(a) Using a graphing utility, draw a scatter diagram of the data treating temperature as the independent variable. What type of relation appears to exist between temperature and chirps per second?

(b) Based on your response to part (a), find either a linear or quadratic model that best describes the relation between temperature and chirps per second.

(c) Use your model to predict the chirps per second if the temperature is 80°F.