The combined resistance 
of two resistors of resistances 
and 
connected in parallel is given by the formula
Which statement is used in the derivation of this formula?
The currents through the two resistors are equal.
The potential difference across each resistor is the same.
The supply current is split between the two resistors in the same ratio as the ratio of their resistances.
The total power dissipated is the sum of the powers dissipated in the two resistors separately.
