I believe your answer is A.
The correct answers are 2, 3 and 6.
The first question is referring to a comparison between founding documents, the analysis of which is wholly related to <em>political science</em> and studies on the organization of a government.
The fourth and fifth questions are specifically inquiring about <em>diplomacy and military combat</em>, so there's not much explanation needed there.
On the other hand, to answer questions 2, 3 and 6 the main thing a historian would need to focus on would be social theory. Matters such as ideological and artistic movements (like the Harlem Renaissance), religious tolerance, racial segregation, and immigration, directly impact how we relate to each other in society.
Hope this helps you out!
Differences:
The Monaco royal family is the Grimaldi dynasty, whereas the Belgium royal family is a constitutional monarchy, similar to that of the United Kingdom. The head of the Grimaldi dynasty is almost always a male, whereas the Belgium royal family should preferably have both a king and a queen. The dynasty was founded in 1160, and the monarchy on 21st July 1831.
Similarities:
Both are European royal families. Both the coat of arms have the same colour tones. Both the families are Catholic.
Answer:
<em>1. Both Whigs and Democrats joined the party.
</em>
<em>2.The party opposed the extension of slavery into the territories.
</em>
<em>5. Martin Van Buren ran as the party’s nominee for president.</em>
Question below!
Why did President Johnson believe that it was important for the United States
to win in Vietnam?
Answer:
<em>Hello, There! I'm here to help!</em>
<em>The Correct Answer Is D. He believed in the domino theory.</em>
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Explanation:
Information to backup My Answer!
President Johnson believed that it was most important for the US to win in Vietnam because communists were spread around the world and Australia and the US feared that the domino theory was becoming true.

Hope this helps!