Question: Why and how did World War I
begin in 1914?

The assassination of Archduke Franz Ferdinand in Sarajevo on 28th June 1914, it triggered a chain of events that resulted in World War 1. After the assassination, Austria-Hungary threatened war on Serbia. ... Germany sided by Austria-Hungary, while Russia sided with the Serbians

Explanation:

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