How do children grow? The pattern of growth varies from child to child, so we can best understand the general pattern by following the average height of a number of children. The table below presents the mean heights of a group of children in Kalama, an Egyptian village that is the site of a study of nutrition in developing countries(data from the Agency for International Development).The data were obtained by measuring the heights of 161 children from the village each month from 18 to 30 months of age. [note:the data below should be one list for Age and one list for height, it was only separated for space saving purposes]

Age in Months	Height in centimetres	Age in Months	Height in centimetres
18	76.1	24	79.9
19	77.0	25	81.1
20	78.1	26	81.2
21	78.2	27	81.8
22	78.8	28	82.8
23	79.7	29	83.5

a)Construct a scatterplot for the data and describe the association between age and height in the study.

b)Calculate the correlation coefficient "r". Does this value support your description in part(a).

c)Find the equation of the least squares regression line.

d) What does our regression line predict for the height of children in Kalama at 32 months of age?

e) What does our regression line predict for the height of children in Kalama at 20 years of age (20 years = 20X12=240 months)?

f) Comment on the validity or usefulness of the predictions in (d) and (e)