the material is hotter & denser
making inferences based on data from seismic waves.
Because it is near the earths crust were is our home
The Chemical Composition of the Earth's atmosphere is important because it holds the Earth together.
STRATOSPHERE
The composition of Ozone layer is O3
the layer of rock that comprises 67% of earths mass
half of earths layer
mantle
The earth thinnest layer is the crust.
The crust is the thinnest layer of the Earth.
Actually, the Troposphere Layer can be considered as Earth's first protective layer, because its well-the atmosphere's first layer. You can think of it that way to remember which is Earths first layer.