Answer: A 
Explanation:
  Because its the main difference between the 2
 
        
                    
             
        
        
        
While adding we need to follow that the units of mass i.e., kilogram and gram are converted into grams before addition and then follow the simple addition process. We can add two or more units of mass given in kilogram and grams like ordinary numbers. Always express grams as 3-digit numbers for example 3 g = 003 g.
 
        
             
        
        
        
I believe the answer is A!
        
             
        
        
        
Answer:
The term niche, when used in the science of ecological biology, is used to define an organism's role in an ecosystem. Not only does its niche include the environment that a given organism lives in, but it also includes the organism's "job" in that environment
Explanation:
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