Answer:
From that statement, it can be inferred that President Reagan's doctrine was that of Deterrence.
Explanation:
Deterrence theory states that a country can become so powerful tat engaging in war with ti assures the destruction of the adversary. It can also applied to two or more countries, which means that these countries would never engage in a mutual war, because they would assure their mutual destruction.
This is exactly what happenend in the Cold War between the United States and the Soviet Union: both countries had so much military power, and especially, nuclear power, that they preffered to avoid any direct confrontation.
What Reagan's speech is saying is that the U.S. should be so powerful, that no country on Earth would even think of starting a war with it.
The workers didn't learn how to completely manufacture a certain item. Instead, they learned a certain part of the process in manufacturing such item and they will repeat such process again and again, all day long. This is how the development of the industry impacted the way people lived and worked.
Was made to share information, ideas, and culture. Astronomical observatories ended up being built as well.
Your answer is A. Republic.
Hope this helps :)