You have a DC circuit hooked up to a 5.0V battery. A single resistor (R1=20 Ohms) is hooked in series with a pair of parallel resistors (R2=40 Ohms, R3=30 Ohms). What is the current flowing through the 30 Ohm resistor?
A. 76.7 mA
B. 135 mA
C. 58.3 mA
D. 500 mA
E. 315 mA