What is the number of chromatids in a chromosome during metaphase?

While examining the mitotic stage in a tissue,one finds some cells with $16$ chromosomes and some with $32$ chromosomes. What possible reasons could you assign to this difference in chromosome number? Do you think cells with $16$ chromosomes could have arisen from cells with $32$ chromosomes or vice versa?

$A$ cell at the telophase stage is observed by a student in a plant brought from the field. He tells his teacher that this cell is not like other cells at the telophase stage. There is no formation of a cell plate,and thus the cell contains a higher number of chromosomes compared to other dividing cells. This would result in:

"Endomitosis" refers to

Arrange these events of mitosis in their correct sequence:
$a -$ Nuclear envelope assembles around chromosome clusters.
$b -$ Spindle fibers attach to kinetochores of chromosomes.
$c -$ Condensation of chromosomes.
$d -$ Centromeres split and chromatids separate.

Agglutination of chromosomes is caused by a mitotic poison called