The correct answer is a dichotomous key. Basically, you use the key to decide what species an organism is by looking at what traits it has, and if it doesn't have some traits you can instantly rule out a large number of species which brings you closer to your answer of what the species is that you're looking at.
        
                    
             
        
        
        
Sources of heat from inside earth is radioactive decay and residual heat.
        
             
        
        
        
The answer is C. These structures are vacuoles and are found in plants cell (you can tell it’s a plant cell because of the outer cell wall in the picture). Vacuoles have a variety of other functions storage of waste products, maintain turgor pressure  for plants support. 
 
        
                    
             
        
        
        
Answer:
B- J, L, K
Explanation:
Wrong Subject but the largest side's opposite angle is the largest if that made sense. For example, KL which is the largest side corresponds to the largest angle <J. 
 
        
             
        
        
        
Answer:
First, we take the owl out, the total number of mouse increases at a higher rate and the chipmunks are also decreasing in numbers. In an ideal ecosystem, both mice (lets call it "a") and chipmunks (lets call it "b") should increase since the restraining factor has been removed. But that is the opposite of what we should see. In that case, we will take the owl to be the "limiting factor" for the rodents.
Am
The rodents will have free movement and exercise their fitness over the area, competition sets in between the two species. So we see, a flourishes while b dies out. This can be viewed most predictably that a has an overall greater fitness and would easily get resources and strive readily, which influences the survival rate for 2.
 Hope you got something in any realm of understanding?