Duration of rage at level 6 or 7?

[BoBoDaClown]

Hey guys,

If splashing 6 or 7 levels of barb:

1) What is the duration of the rage?

2) How many rages

3) What str and con bonus would I get?

For calculation assume all enhancements, and a con of 24.

Approximates are fine.

Cheers!!!