What type of data is analyzed to know the structure of the middle layers of the earth?

The correct answer is seismic waves.

The middle layer of the Earth’s is called mantle. Mantle is dense and hot layer composed of silicate minerals. In the base of mantle secondary earthquakes disappear.  

Seismic tomography is used for the imaging of this layer. It is an imaging technique that uses seismic waves generated by earthquakes to create images of Earth’s structure.

pregnancy happens more and more

i think its control and coordinate because im pretty sure thats what tissue does and the joints are what control movement and then your skeletal/ bones provides portection. hope that .