Ch. 23 concept guide is ready; new podcast.

The chapter 23 concept guide is ready to use. It is way different from the other concept guides, but hopefully it will be useful for studying.

There is a new visual podcast in iTunes U. It is related to a part of the chapter 23 reading.

I will try to make up a mini-quiz to go with chapter 23 by Monday.

ALSO: concept guide coming soon for chapter 24. Maybe Monday you will see that.