Given Sxx=∑(xi−xˉ)2=40S_{xx} = \sum (x_i - \bar{x})^2 = 40Sxx=∑(xi−xˉ)2=40, Syy=∑(yi−yˉ)2=90S_{yy} = \sum (y_i - \bar{y})^2 = 90Syy=∑(yi−yˉ)2=90, and Sxy=∑(xi−xˉ)(yi−yˉ)=30S_{xy} = \sum (x_i - \bar{x})(y_i - \bar{y}) = 30Sxy=∑(xi−xˉ)(yi−yˉ)=30, what is the coefficient of determination R2R^2R2?
0.250.250.25
0.3330.3330.333
0.500.500.50
0.750.750.75