The level of such particulates is measured in micrograms per cubic meter of air.
The level of such particulates is measured in micrograms per cubic meter of air.
微粒的测量方法，是计算1立方米空气里有多少毫克。
The level of such particulates is measured in micrograms per cubic meter of air.
微粒的测量方法，是计算1立方米空气里有多少毫克。