Derived from the inner cells of a human blastocysts , a very early human embryo. 
At the blastocyst stage, five to 10 days after fertilization, 
the embryo is a cluster of 100-200 cells
        
                    
             
        
        
        
Answer:
Frequency of allele A1- 0.41 
Explanation:
In Hardy weinberg equilibrium, 
P refers to the dominant allele 
q refers to the recessive allele
The allele frequency will be p+q=1
The genotypic frequency is- P²+q²+2pq=1
P²= genotype of dominant trait ( A1A1)- 77
2pq= genotype of heterozygotes (2pq)- 65
q²= genotype of recessive trait (A2A2)-  123
Total number of offsprings= 77+  65+ 123
                                             = 265
Now to calculate allele frequency of A1= 

= 77/265 + 1/2( 65//265)
=  0.290+ 0.122
= 0.413
Thus, 0.41 is correct.
 
        
             
        
        
        
A sudden and violent movement of the ground sometimes causing great destruction as a result of movements within the earths crust or volcanic action.
        
             
        
        
        
It helps you follow procedures accurately in order to get higher, more accurate results and become a better medical professional
        
             
        
        
        
The best option is B He used a new experimental method to test his hypothesis.