If you have attempted a question correctly, you can find it in your Correct List. If you have also bookmarked the question, you can find it in your Bookmark List. If you have attempted a question wrongly, it would be available to you in your Revision List 1.
While in Revision List 1 and 2, if you attempt a question correctly, you can find it in next revision list, i.e. Revision List 2 or Revision List 3, as the case may be. While in Revision List 3, if you attempt a question correctly, you can find that question in Correct List.
If you attempt a question wrongly in any revision list (whether Revision List 1, 2 or 3), the question stays in that revision list only. However, it would not be available to you for re-attempting till next 48 hours.
Skipping a Question
If you skip a question in any of the question list, the question would appear next time when you choose that Question List for that chapter.
Going Back in a Question List
You cannot go back in any question list. If you want to revisit the question, follow the instructions given above.