A plane is on its approach to land on the runway. The jet’s height above the ground is given in feet as a function of the time in seconds. The following table tracks the plane as it lands: t (in seconds) h (in feet) 0 4000 5 3500 10 3000 15 2500 20 2000 25 1500 Calculate the slope. Use the formula . What is the significance of the sign of the slope?