You have to apply Kirchhoff's rules to find the current and potential difference. Let's take first loop:
R4
C1
V
R1
R3
R2
I1
I3
I2
I1
I1
fully charged capacitor-no
current going through it
we have that:
V=I1R1 + I3R3 + I1R4
second loop:
I2R2=I3R3
and we know that
I1=I2+I3
If you solve that for I1 you will have the current going through resistor R4
to find the potential difference across the capacitor and its charge we also apply K's rule
We have then:
q/C=I1R4
solve for q , and potential difference is simply V=q/C
Power dissipated by resistor 4:
P=(I1)^2*R