I believe that Cell a is most likely in G1 phase.
The G1 phase, or the gap 1 phase, is the first of four phases of the cell cycle that takes place in eukaryotic cell division. In this part of interphase, the cell synthesizes mRNA and proteins in preparation for subsequent steps leading to mitosis. The phase ends when the cell moves into the S phase of interphase.
        
             
        
        
        
Answer:
I believe you just answered it yourself. they development an immunity to insecticides the more they are exposed to it.
 
        
             
        
        
        
Answer:
During metaphase, the cell's chromosomes align themselves in the middle of the cell through a type of cellular "tug of war." The chromosomes, which have been replicated and remain joined at a central point called the centromere, are called sister chromatids.