assuming this is plate tectonics: At divergent boundaries where the plates pull apart, magma from the earth's mantle fills in the spaces created.
 
        
                    
             
        
        
        
Answer:
mutation in DNA
Explanation:
Mutations are changes in the genetic code that can occur in many ways. Each time a cell divides, say, DNA must be copied into two copies, one copy for each new cell. Although this copying is very precise, it is still not perfect - for about every billion accurately copied databases, one is mistranslated. 
Another source is DNA damage, which can occur spontaneously through the normal life of the cell, or through external toxins or negative influences (ultraviolet radiation, for example). Through evolution, cells have developed a very complex system for repairing changes in DNA, but these systems not only have limitations but can sometimes cause additional errors themselves.
 
        
             
        
        
        
Answer:
The size is reduced as 80-95% of the available energy at one trophic level is not transferred to the next
Explanation:
There is loss of energy as it is transferred between trophic levels. The decrease in energy as it moves up the pyramid is due to energy loss as metabolic heat when one organism is consumed by another from the next level as it moves up the trophic levels.
 
        
             
        
        
        
Answer:  C. Positive feedback mechanisms are overwhelmed.
Explanation:
Homeostasis, is the maintenance of a normal internal environment, in the face of external and internal disturbances, so that the functions of cells and systems of the body are preserved. This is accomplished primarily through feedback systems, so when a system is disturbed, a diversity of local responses, systemic reflexes (rapid reactions and automatic stimuli) and long-term adjustments are activated to bring the system back to its normal equilibrium point.
Most systems are controlled by negative feedback mechanisms, with the controlled variable being able to "turn off" its release, in the same way as a thermostat controls the temperature of a room. So, in this context, too much positive feedback would be related to harmful effects, such as homeostatic imbalance.