Resistors r1, r2, and r3 are connected in parallel. r1 is 68 ohm and r2 is 93 ohm. the equivalent resistance of the parallel combination is 26-ohm. what is the resistance of r3?
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Ohm's law tells you that i = v/r where v is equivalent voltage and r is equivalent resistance of the circuit
since all circuits have the same voltage, your question is really asking which circuit has the lowest total resistance, since the lower the resistance, the higher the current
circuit a has a resistance of 5 ohms; circuit c is in series so has a resistance of 10 ohms; circuit b is in parallel and therefore has a resistance of 2.5 ohms (review your notes on adding resistances in parallel and series); therefore b has the highest current

Ok what do you need with