One example is, PPM indicates "components for each million". If you discover out that the concentration of NO2text NO _2NO2​ is equivalent to one ppm, it signifies that if you take a "sample" of air and divide it into 1,000,000 sections, one of these will include NO2textual content NO _2NO2​. https://benjamink402dyr7.ssnblog.com/profile