The scatterplot shows the relationship between two variables, $x$ and $y$, for data set E. A line of best fit is shown. If the original line of best fit for data set E can be represented by the equation $y=mx+b$, and a new data set G is created by multiplying the $y$-coordinate of each data point from data set E by a positive constant $k$, which of the following describes the equation of a line of best fit for data set G?