What technology was used prior to transistors to amplify a signal? 
Vaccum tubes

How did it change the history of communications in the US? What was the metaphor that the video used to describe how this technology worked?
Telephone services

Describe the break through in the 1947 that made the transistor a reality?
using a double pointed contact on a germanium surface. When the points are put very close together they get a voltage. Water experiment.
What do we learn from watching this video about group and team dynamics that we can apply to our own situation?  You need to respect the  accomplishments of your team members and work with them to accomplish the common goal despite your own personal goals.

What was successful about this team? What was its downfall?
Specialization in fields and being brilliant but thats also the downfall is your huge ego from being brilliant.
What medic and social changes occurred as a result of the transistor?
Hifgher rate flow of information bring people closer together from farther away.