I am having difficulty calculating the Thevenin resistance of this circuit
I know I need to replace the batteries with links but then I am confused about how to approach R1,2 & 3 in terms of being in series or parallel. Would I consider R2 and R1 in parallel and therefore 1*2/1+2 = 0.667 then add R3 as they are is series then treat R4 as parallel?
I'm looking for the Thevenin equivalent as seen across 'A' amd 'B'
Losing the will with this slightly...