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Air pollutants are released into the troposphere where humans live and breathe and often react quickly so change throughout the day.
a.) Why does nitrogen dioxide (NO2) (black line) peak in the morning (Figure A)? (2 pts)
b.) Why does urban ozone (O3) concentration (red line) peak in the afternoon in Figure A? (2 pts)
c.) What would be different about these curves if it was a rainy day? How might these patterns be different on the weekends? (3 pts)
d.) Please explain the decreasing trend of NO2 concentrations in major cities during the onset of COVID in 2020 (Figure B). (3 pts)
