Chapter 13: Hurting, Helping and Cooperating
Read the Chapter 13 outline Implement the Chapter 13 study plan See the class overheads Chapter 13, part 1 Chapter 13, part 2

Websites	Video	News	Handouts
and
The publisher's website Other Websites	Video	Radio Stories The Good Show (Radio Lab) (part of it is on cooperation and the tit-for-tat strategy)