What roles did the tigris and euphrates rivers play in creating a farming surplus?

What best describes the transportation within cities in the early 1800s

Ineed asap! ! what is the name of the system in which each branch of the u.s government can limit the actions of the other branches? a. perpetual union b. division of powers c. cooperative federalism d. checks and balances

Which of these innovations led to increased production in american factories in the early 1800s? a. the use of interchangeable parts b. the construction of canals c. the invention of the mechanical reaper d. the availability of electricity