Social and political consequences of WWI

Name three new weapons that changed how ww! was fought and how?

Match each idea to the correct principle of government. federalism separation of powers checks and balances divides the powers of government into different branches arrowright divides the powers of government between central and state governments arrowright each branch of government has certain powers that prevents the abuse of power on the people arrowright

What river systems the worlds earliest known civilization develop ?