Solution
= Solution
A <preorder> is a <binary relation> that is both <reflexive> and <transitive>: $a\preceq a$ for every $a\in A$, and $a\preceq b\preceq c$ implies $a\preceq c$.
= Solution
A <preorder> is a <binary relation> that is both <reflexive> and <transitive>: $a\preceq a$ for every $a\in A$, and $a\preceq b\preceq c$ implies $a\preceq c$.