For the resistor network to the right, R1 = 10 Ω, R2 = 20 Ω, R3 = 25 Ω, R4 = 15 Ω, R5 = 5 Ω, and ΔV0 = 20 V. Compute the current through R3.
a) 0.4 A
b) 0.6 A
c) 0.8 A
d) 1.0 A