The table shows (lifetime) peptic ulcer rates (per 100 populations) for various family incomes as reported by the 1989 National Health Interview Survey.

a) Make a scatter plot of these data and decide whether a linear model is appropriate.
(b) Find and graph a linear model using the first and last data points.
(c) Find and graph the least squares regression line.
(d) Use the linear model in part (c) to estimate the ulcer rate for an income of $25,000.
(e) According to the model, how likely is someone with an income of $80,000 to suffer from peptic ulcers?
(f) Do you think it would be reasonable to apply the model to someone with an income of $200,000?

Ulker rate (per 100 population) Income $4,000 $6.000 14.1 13.0 $8.000 13,4 $12,000 12.5 $16,000 12.0 $20,000 12.4 $30,000 10.5 $45.000 9.4 $60,000 8.2