How do I simplify this resistor circuit for my homework?

[exitwound]

Homework Statement

Homework Equations

Resistors in Series = R1 + R2 + R3... = Req
Resistors in Parallel = 1/R1 + 1/R2 + 1/R3 ... = 1/Req

The Attempt at a Solution

Studying for a test. This sample exam went pretty well. I am having trouble with 3 out of the 20. I can't figure this one out.

The bottom branch can be combined to be Req = 30 + 30 = 60 Ohms

From there, I can't seem to find a way to combine the rest. I have the answer (B) but I can't collapse the circuit.

 

[mikelepore]

The top right resistor is shorted out, so it has no effect. Imagine that it's erased from the diagram.
The center point and point b are the same point.
You have 30 in parallel with 30 in parallel with (30+30).
1/[(1/30) + (1/30) + (1/{30+30})] = 12 ohms.