Petrifaction happens jvgocg igcgicigcicg
        
             
        
        
        
Answer:
<em>The correct option is B. Alleles</em>
Explanation:
The punnet square can be described as a diagram which shows the outcomes of a cross. A punnet square will help us know what will be the probability for a particular trait to occur in the offsprings.
Genes might have the same or different alleles. If the alleles for a gene are similar in an organism, the organism is said to be homozygous for the trait. If the alleles are different, then the organism is termed as heterozygous. 
A dominant allele is the one which which suppresses the effect of the recessive allele. A recessive allele gets masked by a dominant allele. 
 
        
             
        
        
        
Answer:
C. Oxygen & Hydrogen. 
Explanation:
The body is made of 65% Oxygen, 18% Carbon, 10% Hydrogen, 3% Nitrogen, and 4% other elements. 
 
        
             
        
        
        
Answer:
got this
Explanation:
The book called "On the Origin of Species"
 
        
             
        
        
        
Explanation:
the most common gas in the atmosphere is nitrogen and oxygen followed by CO2 etc...