This is one over the square root of two. One divided by the square root of two, which gets us to, so if we round to the nearest thousandths, it's roughly 0.707. So approximately 0.707. And if you wanted to visualize that, one standard deviation of the residuals below the line would look like this. And one standard deviation above the line for any given x value would go one standard deviation of the residuals above it. It would look something like that. And this is obviously just a hand-drawn approximation.