How Do I Simplify This Circuit for My Test Preparation?

[dado]

I'm learning and preparing myself for test, but I'm stuck. I don't know how to simplified this

[PLAIN]http://img814.imageshack.us/img814/4977/42625320.png

 

[elibj123]

Noticed how each of R6,7,8 has one end connected to E2+ and the other connected to E2-? So Actually they're parallelly wired to E2.

You have the same for R3,4,5 and E1.

That actually leaves you with a pretty simple circuit, which I'll let you draw on your own.

 

[dado]

thanks