Please help!

The EPA sets national air-quality standards for common air pollutants. The table shows the change in the concentrations of these pollutants over time and the impact on overall air quality. Reducing which pollutant resulted in the most air-quality improvement?

A. CO(carbon monoxide)

B. O3 (ozone)

C. Pb (lead)

D. NO2 (nitrite)

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.

is in the form atp or adenosine triphosphate

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