Answer: So that the experimenter is able to compare and contrast between the control group and the variable group. This will help the experimenter come up with data conclusion during their experiment:) 
 
        
             
        
        
        
Answer: 25 %
Explanation:   Adenine and Thymine are base pairs in DNA chain.
So their amounts are equal.
 
        
             
        
        
        
Answer:
yes 
Explanation:
 it was because it was Minoans first European civilization which obviously originated from Europe. 
 
        
             
        
        
        
Tropopause is the boundary between the troposphere and stratosphere.
Explanation:
- Tropopause marks the transition region between troposphere and stratosphere.
- As we move up from the Earths surface , the temperature gets colder but when we reach the tropopause the temperature becomes constant and the temperature does not fall further.
- It is at a height of about 9Km at the polar region while at a height of 17 Km at the equitorial region.
 
        
             
        
        
        
Answer:
they are transmitted by one person to another, like kissing, coughing, sneezing, or any physical contact from the infected person to someone who's not.