Arches were very important for building

good things

Explanation:

montesquieu took the view that the roman republic had powers separated so that no one could usurp complete power. in the british constitutional system, montesquieu discerned a separation of powers among the monarch, parliament, and the courts of law.

the treaty of brest-litovsk was a peace treaty signed on 3 march 1918 between the new bolshevik government of russia and the central powers (german empire, austria-hungary, bulgaria, and the ottoman empire), that ended russia's participation in world war i.