Answer:
Stratosphere
Step-by-step explanation:
This layer is the second one above from the sea level. The first layer is the troposphere, it runs from the sea level until 10 km above. The second one, the Stratosphere, is the one that runs from 10 to 50 km above sea level. In this layer is where most of the airplanes fly, also is where the ozone layer is located. In this layer the gravity force is still present and is the layer in which the X rays and ultraviolet waves that comes from other celestial bodies, can still reach this layer, but they can not pass to the Earth surface.
Hope this info is useful.