These questions were primarily designed to get you thinking about plate tectonics, which is probably the single most important topic in ES 10. If you take nothing else with you from this class, we would like you to take away some understanding of plate tectonics.
From reading your answers to these questions, it seemed that the single area which gave people the most trouble was the distinction between questions 2 and 3. I hope that this distinction will become clear after you read the answers to questions 2 and 3. However, here's a sneak preview: the answer to question 2 can be found in Chapters 1 and 19 of your textbook, particularly figure 1.6, and the answer to question 3 can be found in Chapter 20, particularly figure 20.27.
The only other problem was that many people wrote answers which were far longer than they really needed to be. These were meant to be short-answer questions. Short, annotated lists would have been just fine; I didn't knock off points for excess length, though.