What new weapons and technology were developed during World War I? A. planes, trains, and automobiles
B. machine guns and rockets
C. nuclear weapons and satellites
D. machine guns, tanks, and zeppelins

. political or economical policy that isolates a country from participating in international relationships. it has been suggested that the united states participates in isolationism because of its lack of involvement in particular wars or alliances.

the system of checks and balances is very important to the us constitution. it makes sure that all three branches of government have limited power. that they do not have too much power. with this system they can limit the amount of power that each one has. that way no branch becomes too powerful.

an example of this is how the executive branch can veto bills from the legislative branch but the legislative branch can still override that veto. the name checks and balances come from the power for one branch to check the   power of another branch to make sure that everything is balanced between all three.

i hope this

i think the answer is d