Transcript text: The blue curve on the following graph shows the height of an airplane over 10 minutes of flight. The two black lines are tangent to the curve at the points indicated by A and B .
The slope of the blue curve measures the plane's $\qquad$ . The unit of measurement for the slope of the curve is $\qquad$
At point $A$, the slope of the curve is $\qquad$ , which means that the plane is $\qquad$ at a rate of $\qquad$ Calculating the slope, pay extra attention to the units of analysis.)