Answer:
A general line can be written as:
y = a*x + b
Where a is the slope, and b is the y-intercept.
if we know that the line passes through the points (x1, y1) and (x2, y2), the slope will be:
a = (y2 - y1)/(x2 - x1)
In this case, we can see that the line passes through the points (0,0) and (4,2) then the slope will be:
a = (2 - 0)/(4 - 0) = 2
Then the equation is:
y = 2*x + b
And because we have the point (0, 0), we know that the y-intercept is equal to zero, then the equation is:
y = 2*x
This means that Pablo does 2 revolutions per feet, and we already found that the slope of the equation is 2.