Which stage of cell division is best for studying the morphology of chromosomes?

$A$ student was asked to identify a permanent slide of mitosis. He made the following observations:
$(i)$ Splitting of centromere and formation of daughter chromatids.
(ii) Chromatids are migrating towards the opposite poles.
The stage would be

The synthesis and storage of $ATP$ molecules required for cell division occur in which phase?

Which stage is indicated by the given figure?

If a diploid cell is treated with colchicine,then it becomes

Decondensation of chromosomes occurs during