What is Vo?
My attempt is nothing more than a guess, and I'm not sure if I'm right:
I think Vo is 0 because current can only flow in a closed loop. Since no current flows into the little "arm" from Vo to ground, the voltage across R2 is 0 and thus Vo = 0 volts. Is this correct?
Also, would this mean that the node at the bottom of this circuit is grounded because Vo = 0? Or would it only be a virtual ground?