Question

12.15--atmosphere practice p.1
the earths layers are divided up by

Explanation:

The Earth's layers (atmospheric, geospheric, etc.) are divided by changes in physical properties like temperature, composition, or pressure. For atmospheric layers, boundaries like tropopause (temp change) separate layers. In geosphere, Mohorovičić discontinuity (composition) divides crust and mantle. The key is identifying the basis: physical properties (temp, composition, pressure) that change at boundaries.

Answer:

The Earth's layers are divided up by changes in physical properties (such as temperature, composition, or pressure) (e.g., atmospheric layers by temperature gradients, geospheric layers by compositional/mechanical changes).