For this case we have that by definition, the equation of the line of the slope-intersection form is given by:

Where:
m: It is the slope of the line
b: It is the cut point with the y axis
We have the following points:

We find the slope:

Thus, the equation is of the form:

We substitute a point and find b:

Finally, the equation is:

Answer:

It's an expression that can be simplified to read
( 0.7 x 0.4 ) ( b³ x b⁹ )
= ( 0.28 ) ( b¹² ) = 0.28 b¹² .
The answer to the question is 1.9 million in 1950.