The slope of the blue curve measures the plane's rate of descent ▼ . the unit of measurement for the slope of the curve is feet per minute at point a, the slope of the curve is rate of analysis.) which means that the plane is at a feet per minute. (hint: calculating the slope, pay extra attention to the units of at point b, the slope of the blue curve is a rate of analysis.) which means that the plane is at feet per minute. (hint: calculating the slope, pay extra attention to the units of