In the circuit in the figure, the emf of the battery is 20V. All the inductors are of the same inductance, L = 0.05H, and of negligible resistances. The resistances of the resistors are Ro = 3R = 1S = 4R = 4R = 4R = 5Re = 3. The switch S is closed at the time t = 0. What is the current flowing in Ro long after the switch S is closed?
4A
5A
2.5A
3A
8A