The line graph illustrates the amount of nitrogen oxide produced by four different types of vehicles at various speeds. Overall, it is clear that buses are the highest emitters across all speeds, while diesel cars produce the lowest emissions. Additionally, all vehicles show a similar pattern where emissions are highest at very low and very high speeds.
Data Detail 1: High Emitters
Buses and lorries follow a similar U-shaped trend. Bus emissions start at 40 g/km at the lowest speed, drop to a minimum of approximately 28 g/km at 60 kph, and then rise back to over 40 g/km at 130 kph. Lorries follow this pattern at a slightly lower level, reaching their lowest emission point of 20 g/km at around 80 kph.
Data Detail 2: Low Emitters
In contrast, petrol and diesel cars emit significantly less nitrogen oxide. Petrol cars remain relatively stable, fluctuating between 10 and 12 g/km. Diesel cars are the most environmentally friendly in this metric, with emissions consistently staying below 10 g/km, reaching a low of roughly 5 g/km between 60 and 100 kph.
