Use division to find the factors of $28$.

$5$ is a factor of $15$.

$6$ is a factor of $9$.

$0$ is a factor of $4$.

$1$ is a factor of every number.

Every number is a factor of itself.

A bookshop helper has to keep $36$ books in equal piles. What are the different piles of equal numbers that he can make?

The PT teacher is making his class of $40$ children stand in rows. What are the different number of rows he can make, such that each row has the same number of children?