Answer:
Chromosomes condense before mitosis to allow them the ability to move smoothly, without becoming entangled and breaking. (So, they are conveniently packaged for cell division, in which the chromosomes must move to both poles of the cell.)
Explanation:Otherwise it would be a mess as they get tightly packed
Answer:
Option D, Zinc is higher on the activity series because there is clear evidence of a reaction.
Explanation:
It is very clear that a metal which is higher in activity will replace a metal having lower activity.
Since, Zinc has higher activity than copper, it is very sure that it in a copper chloride solution it will replace copper and produce zinc chloride solution leaving behind copper as residue.
Residues of copper is a clear evidence of reaction
The chemical equation for this reaction would be -
Hence, option D is correct
I do not know at ALL. =( Sorry.