Faculty salaries. Here are the salaries for a sample of professors in a mathematics department at a large midwestern university for the academic years 2010-2011 and 2011-2012.
(a) Construct a scatterplot with the 2011-2012 salaries on the vertical axis and the 2010-2011 salaries on the horizontal axis.
(b) Comment on the form, direction, and strength of the relationship in your scatterplot.
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(c) What proportion of the variation in 2011-2012 salaries is explained by 2010-2011 salaries?