Science / Weather / Air: This is considered the mixture of gases that make up the earth's atmosphere. The principal gases that compose dry air are Nitrogen (N2) at 78.09%, Oxygen (O2) at 20.946%, Argon (A) at 0.93%, and Carbon Dioxide (CO2) at 0.033%. One of the most important constituents of air and most important gases in meteorology is water vapor (H2O).
Air Noun Synonyms: atmosphere, ambience, aura, climate, feeling, sense, mood, quality
Business / Construction / Run, Stair: The horizontal distance of a stair tread from the nose to the riser. MORE
Life Style / Travel / Airlines Reporting Corp (Arc): The airlines reporting corporation is responsible for supervising payments from travel agencies to airlines along with the manner in which tickets are issued to consumers. MORE