Refer to the study of poor growth in children from Exercise 17.37. Consider only those boys and girls who were below norms for their age groups. That is, ignore those who turned out to have normal heights according to growth charts.

a. Among only children who are below height norms, calculate the relative risk of having an underlying medical condition if one is a boy as opposed to a girl. Show your calculations.

b. Explain what we learn from this relative risk.

c. Now calculate the relative risk of having an underlying medical condition if one is a girl. Show your calculations.

d. Explain what we learn from this relative risk.

e. Explain how the calculations in parts (a) and (c) provide us with the same information in two different ways.