Final answer:
Airplanes travel in the troposphere to avoid weather conditions in other layers of the atmosphere.
Step-by-step explanation:
The layer of the atmosphere that airplanes travel to avoid weather conditions is the troposphere.
The troposphere is the lowest layer of the atmosphere, extending up to about 7-20 kilometers above the Earth's surface. It is where weather phenomena occur, such as clouds, precipitation, and winds. Airplanes fly in the troposphere to avoid severe weather conditions that may exist in the other layers of the atmosphere.
For example, flying above the troposphere and into the stratosphere, where the ozone layer is located, would expose airplanes to high levels of radiation. Similarly, the mesosphere above the stratosphere experiences extremely low temperatures and strong winds, making it inhospitable for aircraft.
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