Solution
= Solution
The <binary relation> $\leq$ is reflexive and transitive but is not a <symmetric relation>. For example, $1\leq2$ while $2\nleq1$. Therefore
$$
\boxed{\leq\text{ is not an equivalence relation on }\mathbb N.}
$$
There are consequently no <equivalence classes> for this <binary relation> in the requested sense.