Small fixes of typos in W&W section 6.222 Exercise 5 and 6.

I fixed two sets of minor typos.

Two Questions:
1) Are you going to link to references W&W mention? If so, how can I help you as I find such references as part of my work?

2) Are you comfortable with me using your work on Chapters 6 and 7 as a starting point for mine? I would add a "BASED ON A TRANSCRIPTION BY BRIAN WIGNALL" with a link to your repository at the bottom of each web page.