Suppose the correlation coefficient for a set of data is $r=0.725$. What is the coefficient of determination $r^2$? What percentage of the variation in the data is explained by the regression line, and what percentage is unexplained?

$r^2=0.495$

Explained variation $=49.5\%$

Unexplained variation $=50.5\%$

$r^2=0.583$

Explained variation $=58.3\%$

Unexplained variation $=41.7\%$

$r^2=0.595$

Explained variation $=59.5\%$

Unexplained variation $=40.5\%$

$r^2=0.526$

Explained variation $=52.6\%$

Unexplained variation $=47.4\%$