Epimorphism that is Split Monomorphism is Split Epimorphism

Theorem
Let $\mathbf C$ be a metacategory.

Let $f: C \to D$ be a epimorphism and a split monomorphism.

Then $f: C \to D$ is a split epimorphism.

Proof
Dual proof of Monomorphism that is Split Epimorphism is Split Monomorphism.