Answer :Erwin Chargaff   a Biochemist
Explanation:
He formulated the base paring of double helix of DNA. He reasoned that since the percentage of four  DNA  bases are of this proportions in human;
                                   Adenine=30.9% and Thymine =29.4%;
                                   Guanine=19.9% and Cytosine =19.8% 
Then,  the amount of adenine will always be equal to thymine,
And the amount of Guanine equals to cytosine based on this percentages of distribution.  
(Adenine and Guanine are large, molecule of Purines, while thymine and Cytosine are Pyrimidine)  
  
He concluded (although scientist believed, he did not explicitly stated this) that this should be the base paring patterns in DNA molecule. This is the first Chargaff Rule.
His second rule is that the DNA composition, in the relative amount of the four bases Adenine, Thymine, Cytosine and Guanine varies in proportion from one organisms to another. And this is the basis of molecular diversity.
 
        
             
        
        
        
Answer:
C.) Selective pressure
Explanation:
Selective pressure is a natural process that occurs in nature in which certain phenotypes are favored in certain environments. When we say these phenotypes are favored, this means individuals with these phenotypes have a better chance at survival and reproduction in particular environments. Certain phenotypes may be beneficial in some environments but harmful in others. 
 
        
                    
             
        
        
        
Answer:
15
Explanation:
Since the law of conservation of mass applies to all the chemical reactions this will also end in 10+5 equalling 15 grams
 
        
             
        
        
        
Answer: Hardy Weinberg
Explanation:
Genotype of the person are the characters that are can be defined as the genes that is responsible for certain traits. 
Hardy Weinberg Rule states that if there is a random mating in the population then the genotype and allele frequencies in a population will remain constant from generations to generation in the absence of the evolutionary forces.
Hence, the correct answer is Hardy Weinberg.
 
        
             
        
        
        
Lines up in the middle of the cell