What happened to the air quality for a few months in many parts of the world when a lot of economic activity was shut down during the early days of the pandemic in 2020? Group of answer choices we don't know because we only monitor air quality in cities in the US it improved due to humans creating fewer pollutants from commuting, industrial activities, power generation, etc there was no detectible change in air quality because nature contributes more pollutants than humans it improved but it was unrelated to shutting down of human activities