Answer:
There are many such contributions, but one of the greatest ones was by Nikola Tesla, a serbian immigrant who brought the AC (Alternating Current) uprising to America, despite the efforts of many reputed scientists.
Explanation:
Nikola Tesla provided many examples as to how Alternating Current was superior to DC (Direct Current), as in reduced physical contact, greater efficiency, and a wider range of applications.
The correct answer is B, as at the conclusion of the Spanish-American war, the United States gained an empire and new stature in world affairs.
In fact, as a result of the defeat, Spain ceded its territories of the Philippines, Guam and Puerto Rico to the Americans. In this way the US obtained territories in strategic points of the world (Caribbean, Oceania and Southeast Asia), with which its power in front of the rest of the nations was increased.
In addition, the fact of having defeated a colonial power gave the United States a new status as a world power, both politically and militarily.
In the South it didn't stop some states from preventing the Blacks to vote
Montesquieu concluded that the best form of government was one in which the legislative, executive, and judicial powers were separate and kept each other in check to prevent any branch from becoming too powerful. He believed that uniting these powers, as in the monarchy of Louis XIV, would lead to despotism.
