Answer:
American and Canadian railroads begin using four continental time zones to end the confusion of dealing with thousands of local times.
Explanation:
The British government did<span> not want American colonists crossing the Appalachian Mountains and </span>creating<span> tension with the French and Native Americans. but idk</span>
The above system of United States Constitution is showing three organs of the state i.e Legislative branch, Executive branch and the Judicial branch.
And below each division, their works are given. Aswecan were that, each of the organ is at same height which shows that they are practicing equal powers and they don't interrupt in each others work.
They practice the system of <u>Checks</u><u> </u><u>and</u><u> </u><u>Balances</u> to ensure that none of the organ is enjoying and grabbing too much.
So, the most appropriate option is:

Checks and balances system.
And, we are done !!
#CarryOnLearning...
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