A scatter plot of $N=500$ points shows a relationship between $X$ and $Y$. The regression line is $\hat{y} = 2.5x + 10$. The total sum of squares is $SST = 4000$ and the sum of squared errors is $SSE = 1200$. What is the coefficient of determination $R^2$ and the Pearson correlation coefficient $r$ (assuming positive correlation)?