Taiwan became important because an exile government of China was formed there that claimed to be the rightful government of China. This caused China to have two governments, one that ruled China which was the communist one and one in exile which claimed their right to have power over China but couldn't actually use that power in any way. The problem still exists today and other countries have mostly been neutral on this question.
Answer:
a. mobile phones
Explanation:
One day some engineers decided to change the course of history. Thinking of a way to make communication more efficient and easy, they had the brilliant idea of creating a system that would be capable of communicating between cordless phones. The idea was not bad, but the technology of the time did not help much.
The real history of the mobile phone began in 1973, when the first call was made from a mobile phone to a landline. It was from April 1973 that all theories proved that the cell worked perfectly, and that the cell phone network suggested in 1947 was designed correctly. This was a not very well known moment, but it certainly was a fact marked forever because it was the moment that facilitated communication for most people through the creation of the mobile phone.
America's view in the Vietnam was fear. Fear drove them to participate in the war. Why fear? They were afraid Vietnam would become communist because if they became communist they would support or have the support from the Soviets. If this were to happen Vietnam could've became a missile launching spot for the soviets if America wouldn't have participated.
It's my best explanation from what I remember and from what I think. Hope it's helpful to you.
Q1) Command of the Army act
Q2) Tenure of office act
Q3) Seven Martyrs
Q4) Fifteenth Amendment