While on a trip, you notice that the video screen on the airplane, in addition to showing movies and news, records your altitude (in kilometers) above the ground. as the plane starts its descent (at time x = 0), you record the following data: time, x (min.) altitude, y (km) 0 12 2 10 4 8 6 6 8 4 10 2 if you were to graph this information, the resulting line would represent a linear function. using this information from the table and the information on your graph, by how much does the altitude of the plane change for each three-minute change in time during the descent.