Which of the following statements is true for circuits of multiple resistors? (i) Resistors in series must have the same current running through them (ii) The current through each resistor in parallel must sum to the total current entering that portion of the circuit. (iii) Resistors in parallel must have the same voltage across them. (iv) The sum of the voltages across each resistor in series must sum to the total voltage across that portion of the circuit. (v) Adding an additional resistor in parallel will always reduce the equivalent resistance of that portion of the circuit.