The article “Reduction in Soluble Protein and Chlo rophyll Contents in a Few Plants as Indicators of Automobile Exhaust Pollution” (International Journal of Environmental Studies [1983]: 239–244) reported the following data on x 5 distance from a highway (in meters) and y 5 lead content of soil at that distance (in parts per million):

x 10.85

a. Use a statistical computer package to construct scatterplots of y versus x, y versus log(x), log(y) versus log(x), and 1 y

versus 1

x

.

b. Which transformation considered in Part

(a) does the best job of producing an approximately linear relationship? Use the selected transformation to predict lead content when distance is 25 m.