by superposition method we can find current in R5
here first let say only 2V battery is present in the circuit
now the equivalent resistance to be found for which we can say
2.2 k ohm and 1 k ohm is connected in parallel
now it is in series with 1 k ohm and then that part is in parallel with 2.2 k ohm
now the current flowing through the battery is
now this will divide into R3 and R2 so current flowing in R3 will be
now this will again divide in R4 and R5
so current in R5 will be
now when only 3 V battery is present in the circuit
R1 and R2 is in parallel and then it is in series with R3
so parallel combination will be
also after its series with R3
now it is in parallel with R5 on other side
now current through the battery will be given as
now it is divide in r2 and R5
so current in R5 is given as
now the total current in R5 will be given by super position which is
so there is 0.85 mA current through R5 resistance