A string of five series resistors is connected across a 6 V battery. Zero voltage is measured across all resistors except R_{3}. The voltage across R_{3} is

A certain series circuit consists of a 1/8 W resistor, a 1/4 W resistor, and a 1/2 W resistor. The total resistance is 1200 . If each resistor is operating in the circuit at its maximum power dissipation, total current flow is

The following resistors (one each) are connected in a series circuit: 470 , 680 , 1 k, and 1.2 k. The voltage source is 20 V. Current through the 680 resistor is approximately