Band 6+: The chart below shows the nitrogen oxide emissions of four different vehicles at different speed. Summarize the information by selecting and reporting the main features, and make some comparisons where relevant.

The chart illustrates the nitrogen oxide emissions from four vehicle types—diesel cars, gasoline cars, trucks, and buses—across varying speeds ranging from 0 to 130 km/h.

Overall, diesel cars emit the least and most stable amount of nitrogen oxide out of the four across different speed. Buses and trucks emit the most, slump the emission amount down to a certain speed then increased again.

In detail, diesel cars begin their emissions at approximately 7 units at 10 km/h, while gasoline cars start at around 11 units at the same speed. Diesel cars’ emissions slightly decrease to 5 at 60 km/h and stayed stable from 70 to 130 km/h. Conversely, gasoline cars experience minor fluctuations of emissions throughout the speed range, and conclude just below 8 units at 130 km/h.

Trucks’ emissions commence at roughly 32 units and slowly declining to around 17 units at 90 km/h, whilst buses follow a similar yet less fluctuant trajectory, starting at 40 units and plummeting to 26 units at 60 km/h. However, both types of vehicles experience a sudden increase, with trucks escalating to 25 units and buses climbing to roughly 43 units while running at 130 km/h.