39. Refer to the previous exercise In view of these assumptions. indicate winy such a model would or would not be good in the following situations

a) X = time, percentage unemployed workers in the United States. (Hiru Docs this continually tend to increase or decrease?}

b) X = income, y = charitable contributions within the previous year. (Hint. Would poor people show as much variation as wealthy people")

c) Xage. Yannual medical expenses. (Hint: Suppose expenses tend to be relatively high for the newborn and for the elderly.)

d) x = per capita income. I life expectancy, for nations. (Hint. The increasing trend eventually lev cis off.)