More data on mice. For a biology project, you measure the tail length

(centimeters) and weight (grams) of 12 mice of the same variety.

(a) Explain why you expect the correlation between tail length and mouse weight to be positive.

(b) The mean tail length turns out to be 9.8 centimeters. What is the mean length in inches? (There are 2.54 centimeters in an inch.)

(c) The correlation between tail length and mouse weight turns out to be r =

0.6. If you measured length in inches instead of centimeters, what would be the new value of r?

Figure II.3 plots the average brain weight in grams versus average body weight in kilograms for many species of mammals. There are many small mammals whose points at the lower left overlap. Exercises II.11 to II.16 are based on this scatterplot.