Final answer:
Earth's layers can be defined by their chemical compositions, such as the crust, mantle, and core, or by their physical properties, which lead to designations like the lithosphere and asthenosphere.
Step-by-step explanation:
Earth's interior layers can be defined by their chemical compositions or by their physical properties. Specifically, the Earth is divided into the core, mantle, and crust based on chemical composition. Each layer has distinct chemical elements and compounds. In terms of physical properties, Earth can be divided into the lithosphere and asthenosphere. The lithosphere encompasses the crust and the upper mantle and behaves as a rigid, brittle solid, while the asthenosphere is found beneath the lithosphere and consists of partially molten upper mantle that behaves in a plastic and flowing manner.
The correct answers to how Earth's layers can be defined are:
- By their chemical compositions
- By their physical properties
The terms crust, mantle, and core are distinguished by what elements and compounds they contain, whereas the lithosphere and asthenosphere differ based on how they mechanically behave or move.