Answer: C. 1.8
Steps:
25x = 45
x = 45/25
x = 1.8
        
             
        
        
        
D) Stem cells are usually harvested from embryos.
        
                    
             
        
        
        
Answer:
The correct answer is - Sustainable development.
Explanation:
Sustainable development is the process of using or utilizing the natural resources in the present in such an efficient way that there will be resources for future generations without compromising their needs.
It is essential in the current situation as people overexploiting the natural resources that it is quite possible there will very few resources will be left for future generations.
 
        
             
        
        
        
Answer:
Complete dominance Result from successive mutations of the same GENE.
Explanation:
 
        
                    
             
        
        
        
Sister chromatids have different alleles although carry same genes on same loci. So if it doesn't happen so, like if there are same alleles on sister chromatids then there is a problem in its formation. i.e., male and female alleles haven't contributed equally ( may be an error during their segregation process ). And obviously it doesn't happen in a real cell so we must understand this point. Because normally whenever it happens there's one half from the male and one half  from the female. (i.e. maternal and paternal alleles contribute equally).
 I hope you get the answer!!!