advanced practice nurse a registered nurse having education beyond the basic nursing education and certified by a nationally recognized professional organization in a nursing specialty, or meeting other criteria established by a Board of Nursing.
Quick Answer. The air that makes up Earth's atmosphere contains 20.9 percent oxygen. This is true up to about 70,000 feet above sea level. However, above 10,000 feet, the atmosphere becomes too thin to support human life, even though its proportions do not change much. Continue Reading.
A: Only 0.000053 percent of air is composed of hydrogen, making it the ninth most prevalent gas in the air. Nitrogen takes the lead, making up 78.084 percent of air, more than one million times more space than hydrogen. Oxygen also makes up a large part of air at 20.947 percent.