..............4 is D and 6 is A
        
             
        
        
        
Answer: equilibrium phenomenon
Explanation:
 
        
             
        
        
        
Answer;
A.Vinegar and soda
Explanation;
-A salt is a substance that contains a cation which is a metal ion or an ammonium ion and an anion derived from an acid. It is an ionic compound that can be formed by the neutralization reaction of an acid and a base.
 
        
             
        
        
        
I believe that on the Naive B-cell the antibodies exist as transmembrane proteins. A naive b-cell is a type of b-cell that has not been exposed to an antigen. When exposed it becomes either a memory B cell or a plasma cell that secrete antibodies  specific to  the antigen that was originally bound.