The pet shop wants help organising its products.

$($b$)$ Design a relation S from the set B to itself which is a $($non$-$empty$)$ equivalence

relation. Describe your relation first in words, then specify its elements using

ordered pairs. Explain how you know that it is an equivalence relation, and

how this equivalence relation might help the pet shop organise its products.

$($Continue answer on page $4$ if necessary.$)[4]$

a S b means $$Product a $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$

S $=$