hesolomon, I answered "no, because it remains a third phase" and was correct. I have no idea what this means in English but it seems, if my answer was correct I would think "stage" should also have been accepted?
"No, because each third is for Papa." I murdered this one. When did we learn "etapa"? And I love it that quedarse isn't being used reflexively, too. I have not seen that before. Tough sentence. I probably should have lost two hearts instead of just "una tercera" (a third of my three). Didn't help that the recording was on the accelerated speed.
'Quedar' is not always reflexive. Perhaps later on we'll learn more about how that works to clarify.