One example is, PPM indicates "areas per million". If you discover out which the focus of NO2text NO _2NO2​ is equal to one ppm, it implies that if you're taking a "sample" of air and divide it into 1,000,000 components, one of them will consist of NO2text NO _2NO2​. Can https://jasperxzxur.ampblogs.com/how-much-you-need-to-expect-you-ll-pay-for-a-good-free-ppm-calculator-73409744