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Quiz - Indian Inventors Offer Nose Filters to Fight Heavy Air Pollution
January 18, 2018
Question 1 / 4
What does the Environmental Protection Agency define particulate matter as?
Inhalable particles with diameters that are 3 micrometers and larger.
A mixture of solid particles and liquid droplets found in the air.
Strands of human hair that are larger than PM 2.5.
Breathing that includes dust and air pollutants.
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Quiz - Indian Inventors Offer Nose Filters to Fight Heavy Air Pollution
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