Solution (source code)

= Solution

The matrix in part (d) has trace $4$ and determinant $1$. Since $|\operatorname{tr}\phi_*|>2$, the once-punctured-torus case of the <Nielsen–Thurston classification theorem> says that $\phi$ is pseudo-Anosov. The <Hyperbolization of a pseudo-Anosov mapping torus> therefore gives
$$
\boxed{\operatorname{int}M_{\mathcal H}\text{ is a complete finite-volume hyperbolic three-manifold}.}
$$