https://blog.gongquiz.com/2021/04/01/25%e2%84%83-1atm%ec%97%90%ec%84%9c-0-21mol%ec%9d%98-o2%ec%99%80-0-79mol%ec%9d%98-n2%eb%a1%9c-%eb%90%9c-%ea%b3%b5%ea%b8%b0%ed%98%bc%ed%95%a9%eb%ac%bc%ec%9d%98-%ea%b0%80%ec%8a%a4%ec%82%b0/