Section 5.1

10. The weights of children in the Egyptian village of Nahya were recorded. Here are the mean weights of the 170 children in that village:

Age (months)	1	2	3	4	5	6	7	8	9	10	11	12
Weight (kg)	4.3	5.1	5.7	6.3	6.8	7.1	7.2	7.2	7.2	7.2	7.5	7.8

a. Make a scatter plot of mean weight against age. b. Is there a positive or negative association between the two variables? If so, which? c. Does this data describe a linear trend? d. Would you be willing to predict the weight when age = 25 months? Why?

Section 5.3

16. A wildlife biologist is interested in the relationship between the number of chirps per minute for crickets (y) and temperature. Based on the collected data, the least-squares regression line is y =10.53 + 3.41x , where x is the number of degrees Fahrenheit by which the temperature exceeds 50 . Give a sentence that describes the meaning of the slope of the least-squares regression line.