The Attempt at a Solution
I am not getting this at all. I know that I need to calculate the open circuit voltage Voc and the short circuit current Isc. I really have no idea how to find Voc. There is some conceptual leap I need to make here. When the circuit is "open" across a-b, I know that no current flow through the 2 ohm resistor and this allows me to find the current flowing through the left loop (which is = 0.5 A ). But I have no idea how that helps me to find Voc = Vab which is outside of that loop.