Answer:
The expansion of the railroads in the late 1800s was instrumental in helping the US economy boom. It did this in two ways. First, the railroads created a tremendous amount of demand for goods and labor on their own. As the railroads were being built, they needed huge numbers of people to build them.
Having only one branch means that they cannot have checks and balances and separation of power.
Judicial review refers to the power of checks and balances - the Supreme Court can review the constitutionality of the executive and legislative branches of the government.
Manifest Destiny supporters would be in favor of D acquiring land west of the Mississippi river. Manifest Destiny is the belief that America should take land from the Atlantic to the Pacific ocean.
In Asia, different leaders used different ruling techniques. Depending on the time period of this question, you can use China, with points about their bureaucracy and their civil exam system (where you have to be intelligent to be in the government). You can use the Japan and their Tokugawa system. They had a ranking of people like the Samaria and leaders. That’s how they exercised their power.