Slope of the line through $$$\left(4, 5\right)$$$ and $$$\left(9, 7\right)$$$

The slope of a line passing through two points $$$P = \left(x_{1}, y_{1}\right)$$$ and $$$Q = \left(x_{2}, y_{2}\right)$$$ is given by $$$m = \frac{y_{2} - y_{1}}{x_{2} - x_{1}}$$$.

We have that $$$x_{1} = 4$$$, $$$y_{1} = 5$$$, $$$x_{2} = 9$$$, and $$$y_{2} = 7$$$.

Plug the given values into the formula for a slope: $$$m = \frac{7 - 5}{9 - 4} = \frac{2}{5}$$$.

The slope of the line is $$$m = \frac{2}{5} = 0.4$$$A.