Discuss the relationship between Nick and Jordan Baker. How does it reflect, if at all, on the story of Gatsby and Daisy?

There are some similarities although Jordan and Nick are slightly less intense. Both Jordan and Daisy are self-centred opportunists. They seek the most "fun" they can get the quickest way possible. Both Gatsby and Nick and Tom merely facilitate their self indulgences.

Check out this quote which pretty much sums these girls up,

"Sometimes she (Daisy) and Miss Baker talked at once,...as cool as their white dresses and their impersonal eyes in the absence of all desire...making only a polite pleasant effort to entertain or to be entertained. They knew that presently dinner would be over and a little later the evening, too, would be over and casually put away."