The blue curve on the following graph shows the height of an

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. 40 35 30 T 25 20 15 10 0 1234 56 78910 TIME (Minutes)

Solution

The slope of the blue curve measure\'s the plane\'s speed i.e. change in height of the plane per minute. The unit of neasurement for the same is feet/minute.

At point A, the slope of the curve is 30/6 = 5 which means that the plane is flying at the rate of 5,000 feet per minute.

At point B, the slope of the curve is 5/2 = 2.5 which means that the plane is flying at a rate of 2500 feet per minute.