Question

its important to note that the earths structure is not static but is always changing. for example, the lithospheres tectonic plates are always moving which causes earthquakes, mountain building, and volcanoes. which layer retains heat from the earths formation and is molten? lower mantle asthenosphere outer core

Explanation:

The outer - core is a molten layer that retains heat from Earth's formation. It is composed mainly of iron and nickel and its liquid state is due to high temperatures and pressures.

Answer:

outer core