Below are four bivariate data sets and their scatter plots. (Note that all of the scatter plots are displayed with the same scale.) Each data set is made up of sample values drawn from a population.

V V 10 1.0 1.0 7.4 10 2.0 2.0 2.0 4.9 3.0 3.0 3.0 3.0 4.0 4.0 4.0 1.7 5.0 5.0 5.0 1.9 6.0 6.0 6.0 1.6 7.0 7.0 7.0 1.8 8.0 8.0 8.0 3.7 9.0 9.0 9.0 5.5 10.0 10.0 Figure 1 10.0 7.8 Figure 2 W m n 1.0 2.9 104 1.0 7.3 10 2.0 4.2 2.0 9.4 3.0 3.5 X 3.0 7.2 X 4.0 5.3 4.0 5.6 X 5.0 4.7 5.0 8.1 6.0 7.3 6.0 5.0 7.0 6.2 7.0 4.5 8.0 7.8 8.0 7.1 9.0 7.1 9.0 5.6 10.0 7.8 Figure 3 10.0 4.0 Figure 4 (a) Which data set indicates a perfect positive linear relationship between its two variables? X (Choose one) (b) Which data set has an apparent positive, but not perfect, linear relationship between its two variables? (Choose one) (c) In which data set is there evidence of a strong nonlinear relationship between the two variables? (Choose one) (d) Which data set indicates the strongest negative linear relationship between its two variables? (Choose one)