How does the fuel consumption of a car change as its speed increases? Here are data for a British Ford Escort. Speed is measured in kilometers per hour, and fuel consumption is measured in liters of gasoline used per 100 kilometers traveled.

Speed (km/h) ...................... Fuel used (L/100 km)
10 .................................................... 21.00
20 .................................................... 13.00
30 .................................................... 10.00
40 .................................................... 8.00
50 .................................................... 7.00
60 .................................................... 5.90
70 .................................................... 6.30
80 .................................................... 6.95
90 .................................................... 7.57
100 .................................................. 8.27
110 .................................................. 9.03
120 .................................................. 9.87
130 ................................................ 10.79
140 ................................................ 11.77
150 ................................................ 12.83

a. Make a scatterplot to display the relationship between speed and fuel consumption.

b. Describe the relationship between speed and fuel consumption.