The line graph illustrates the amount of nitrogen oxide emissions produced by four various automobiles at different speeds.
Overall, at the beginning of the speed range, buses produce the highest amount of nitrogen oxide emissions, while the opposite is true for diesel cars. It is also clear that at the end of the speed range, buses remain dominant.
Buses start with 40 g/km of nitrogen oxide emissions; this trend is the highest. Until 60 km/h, buses experience a dramatic decline and generate 25 g/km. After this speed, there is an upward trend to 130 km/h. At this speed, buses produce 42 g/km of nitrogen oxide emissions and remain dominant. In contrast, diesel cars begin with only 6 g/km. During the period, this figure slightly decreased, and it is 5 g/km at the end of the speed range. This is the lowest.
Petrol cars and lorries start with 32 and 12 g/km of nitrogen oxide emissions, respectively. Petrol cars undergo a gradual decline until 90 km/h. However, these cars’ nitrogen oxide emissions steadily increase and reach 23 g/km. Whereas, the amount of nitrogen oxide emissions fluctuated for lorries.