What is Earth's atmosphere composed of? Why would you die of suffocation if you were to parachute from an airplane at an elevation of \(12 \mathrm{~km}\) without taking an oxygen tank with you?

Earth's atmosphere is made up of several gases, with the most abundant being nitrogen and oxygen. The other gases include water vapor, argon, carbon dioxide, and trace amounts of neon, helium, methane, krypton, and xenon. The approximate percentages of these gases are: - Nitrogen: 78% - Oxygen: 21% - Argon: 0.93% - Carbon dioxide: 0.04% - Trace amounts of other gases: 0.03% Of these gases, oxygen is the most essential for human survival, as it's required for cellular respiration.

The reason why a person would die of suffocation if they were to parachute from an airplane at 12 km elevation without an oxygen tank is due to the fact that air pressure decreases with altitude, and so does the concentration of oxygen in the atmosphere. At 12 km elevation, the air pressure is considerably lower than at sea level. The oxygen concentration in the atmosphere at this altitude is around 10%. This value is insufficient to sustain proper human respiration and, as a result, a person would experience a lack of oxygen (known as hypoxia), which can lead to suffocation and death if he or she does not take an oxygen tank with them. In summary, the Earth's atmosphere is composed mainly of nitrogen and oxygen, with the latter being essential for human survival. At an elevation of 12 km, the concentration of oxygen in the atmosphere is insufficient for proper respiration. Thus, a person would die of suffocation without an oxygen tank in these conditions.