a multi-story or split-level residence where two or more floors are connected by an internal staircase

A customs system where different tax rates are applied to the same imported product depending on its country of origin, usually based on reciprocal agreements between nations.

A teaching method where one teacher handles two or more grades in a single classroom, often used in schools with limited staff or small student numbers.

a multi-story apartment or house with internal stairs connecting the floors; a loft apartment

a system of accounting in which every financial transaction is recorded in at least two different accounts