∑ Vij= 0loopsum of voltage around any loop is 0 V7 + V1 + V5 + V6 =010 + ( -5 ) + (-2.5) + ( -2.5 ) = 0V7 + V1 + v2 + V4 = 010 + ( -5 ) + (-2.5) + ( -2.5 ) = 0 I added V8 from V2 to V4 nodes. We find they are in series since RTOTAL = R1 + R2V8 = V2 + V4-5 = (-2.5) + (-2.5)