\[\begin{array}{ll} \begin{array}{l} \begin{array}{l} \phantom{-}1680 \\ \quad \underline{\square \,\,\,\,\,\,} \\ \end{array} & \left| \begin{array}{l} \underline{70} \\ \square. \end{array} \right. \end{array} \\ \,\,\,\,\phantom{-}\square \\ \,\,\,\,\,\,\,\,\,\underline{\square} \\ \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,0 \end{array}\]