A line graph on a graph sheet shows the revenue for each year from $1990$ through $1998$ by points and joints the successive points by straight line segments. The point for revenue of $1990$ is labeled $\text{A}$, that for $1991$ as $\text{B}$, and that for $1992$ as $\text{C}$. What is the ratio of growth in revenue between $1991-92$ and $1990-91?$
Statement I: The angle between $\text{AB}$ and $x$- axis when measured with a protractor is $40$ degrees, and the angle between $\text{CB}$ and $x$-axis is $80$ degrees.
Statement II: The scale of $y$-axis is $1$ cm = $1000$.