Yas through elctrochemical signals basically ur right and true X
        
             
        
        
        
Each layer of earth has a different density the more in you go with the layers the more density is going to show up.
Crust-2.2g/cm^3
Upper mantle-3.4g/cm^3
Lower mantle-4.4g/cm^3
Outer core-9.9g/cm^3
Inner core-12.8g/cm^3
Hope I helped in something, Sorry if I didn't gave it my best shot:)
        
             
        
        
        
<h2>
Answer:</h2>
<em>I think during photosynthesis, plants take in carbon dioxide (CO2) and water (H2O) from the air and soil. This transforms the water into oxygen and the carbon dioxide into glucose. The plant then releases the oxygen back into the air, and stores energy within the glucose molecules.</em>