Answer:
a. the virus must be able to cross-link red blood cells directly. 
Explanation:
Viral hemagglutination assay is a method which is used for the quantification of the relative concentration of the viruses.
The principle on which the hemagglutination assay works is as follows:
- There are sialic acid receptors present on the surface of the red blood cells which will bind to the haemagglutinin glycoprotein present  on the surface of the viral particle. 
- Due to the binding of the sialic acid receptors with haemagglutinin particle there will be cross-linking of the red blood cells by the viral particles and a lattice formation will take place. 
- The lattice will remain suspended in the solution however if the concentration of the virus particles will be less, the lattice will settle down in the well. 
Thus, this method allows knowing the relative concentration of the virus. 
<em>Due to its basic principle of cross-linking this method works well for only a few viruses such as influenza virus. </em>
 
        
             
        
        
        
B - Advancements in science can lead to advancements in technology, and technological advancements can also lead to scientific advancements.
        
             
        
        
        
c. Deoxyribose:RNA I think that's right I hope it is I'm sorry if I got it wrong 
 
        
             
        
        
        
Answer:
Translation
Explanation:
When assembled in the nucleus, mRNA peels off and moves to the cytoplasm. Here, it attaches to a ribosome. As the mRNA  moves along the ribosome its information is translated into the appropriate amino acids which are assembled into a polypeptide.
 
        
             
        
        
        
Answer:
one normal girl
One normal boy
One carrier girl
One colour blind boy
Explanation:
Haemophilia is a sex linked feature as it is transmitted with the chromosomes determining sex.
In humans,the male has XY and the female has XX.the Y chromosome is usually genetically empty.so as mall received his Y chromosomes from his father,he cannot inherit his father's sex linked traits .but women can as they receive and X chromosomes from their fathers.so a cross between a carrier woman Cc and a normal man C result in;
XX--CC
XX--Cc
XY--C
XY--c