1. Name two different modes associated with "classic" streams. What is problematic with them?
2. Why are Reactive Streams considered as workable in dynamic pull-push mode?
3. What are the typical building blocks of Akka Stream's graph?
4. How do we convert a graph into a runnable graph?
5. What is the main goal of having materialization as a separate explicit step?
6. Describe the effects of applying different supervision strategies.
7. Which main abstractions provide an Akka Streams TestKit? Why are they useful?