Overall, it is clear that Mexico City is the place with the highest level of pollutants. While in Mexico City and Los Angeles there is a higher amount of NO2 than CO2,  the opposite was true for the other cities.

Looking at the bar chart in more detail,  Los Angeles was primarily contaminated by N2O, with the minimum and maximum N2O ranging from only 39 to 104 micrograms per m3 respectively, but the amounts of SO2 were trivial, standing at only 2 micrograms per m3.  The environment in Mexico City was severely polluted by  the maximum level of N20 emitted was 207 micrograms, nearly doubling the smallest figure. The amount of N2O is a bit higher than the SO2 released, at 200 and 80 micrograms per m3 respectively. 

Turning to figures for other cities,  Calcutta and Beijing have more SO2 emitted into the atmosphere than N20. The maximum figures for SO2 emission were 100 micrograms per m3 in Beijing which was four times as high as the minimum number, with 25 micrograms.  In Calcutta there was a minimum of 47 microgram per m3 and a maximum of 59 micrograms per m3 of SO2. What is more, the disparity between SO2 and CO2 emissions was marginal, N2O was only in the range of 30 to 53.

Overall, as can be seen from the chart, Mexico was the most contaminated city by the 2 mentioned pollutants among four metropolises, whereas, the average presence of air polluting ingredients in Los Angeles was much lower compares to others.

Regarding to the chart, as can easily seen that the average greatest level of SO2 in Mexico amounted to 200 microgram per cubic meter which was over doubled its minimum level. The quantity of S02 poison in Los Angeles was the lowest with both level, accounting for 2 micrograms and 10 micrograms respectively. The daily minimum level of contamination in Calcutta generated by SO2 was 47 micrograms higher than the level of SO2 in Beijing. However, the largest range was just 59 micrograms in Calcutta while the presence of this air pollutant reached 100 in Beijing.

Turing to the second pollutants - N2O appearing more in Mexico. The daily minimum range of N2O in this city was 113, which was almost ten times higher than that of Beijing at approximately 14 micrograms and much higher than the quantity of N2O found in Los Angeles and Calcutta at 39 micrograms and 30 respectively. The upper level of nitrous oxide in Mexico leads the board at 207 micrograms while the quantity of N2O in Los Angeles was just about half of this at 104. The level of N2O in Calcutta and Beijing were nearly the same at 52 micrograms and 54 micrograms respectively.

Overall, Mexico City was the highest level of pollution in the four countries. While Mexico and Los Angeles had a larger amount of N2O than SO2, the opposite of two cities

Looking at the chart in more detail, in Los Angeles, the quantity of SO2 emitted into the atmosphere was the lowest of all cities, the minimum levels were 2 micrograms per m3, five times as high as the maximum levels. The environment in Mexico City was severely polluted by the maximum level of N2O emitted was 207 micrograms, twice as high as the smallest figure. While the amount of highest and lowest of SO2 were lower than 50 micrograms at 10 and 2 micrograms respectively. These amounts in Mexico City were large 50 even if there was a very large gap at 80 and 200 micrograms respectively.

In contrast to Los Angeles and Mexico City, the amount of pollution caused by N2O in Calcutta and Beijing was less than that caused by SO2. The amount of maximum levels of N2O and SO2 in Beijing was higher than that of Calcutta, 54 and 100 micrograms compared to 52 and 59 micrograms in turn. However, it was the opposite for the lowest, the amounts of minimum levels of N2O and SO2in Calcutta was higher than that of Beijing, 30 and 47 micrograms per m3compared to 14 and 25 micrograms per m3

Looking from an overall perspective, it can be readily apparent that Mexico City was by far the most contaminated by the two mentioned air emissions among the four cities. While the quantity of N2O emitted into the atmosphere in Mexico and Ló Angeles was much higher than that of SO2, a reverse pattern was true for the other 2 cities.

Regarding the bar chart, Los Angeles was chiefly contaminated by N2O gas, with maximum and minimum N2O levels of 39 and 104 micrograms per cubic meter, respectively. Meanwhile, the amount of SO2 emission released into the environment is negligible, only about 10 and 2 micrograms per cubic meter for its peak and bottom points, in turn. The maximum amount of SO2 poison in Mexico City was 200 micrograms per m3 which was over twofold in comparison with the figure for its minimum level. The highest quantity of N2O emitted into the atmosphere was 207 micrograms per m3 which was significantly higher than the minimum amount of N2O with 113 micrograms per cubic meter. 

Turning to figures for other cities, the amount of SO2 emission emitted into the environment in Calcutta and Beijing was slightly higher than that of N2O. The maximum quantity of N2O and SO2 released into the atmosphere in Beijing was higher than that of Calcutta, 54 and 100 micrograms per cubic meter compared to 52 and 59 micrograms per m3, respectively. Nevertheless, the opposite was true for the minimum figures, 30 and 47 micrograms per cubic meter of minimum N2O and SO2 emissions in Calcutta was marginally higher in comparison with 14 and 25 micrograms per m3 emitted in Beijing.