Hi all, I've made some ¡­

Hi all, I've made some changes to the notes.

1. I added footnotes on pages 24 and 25.

2. I added a new question, Q23. (so that the old Qt is now Q(t+1) for t greater or equal than 23...)

3. I amended the old Q23 (which is now Q24).

4. In the answers to Q19-Q21 I had misplaced the superscripts. That is now corrected.