Two straight parallel wires are separated by $7\mathrm{.}0$ cm There is a $2\mathrm{.}8-$A current flowing in the first wire.

Part A

If the magnetic field strength is found to be zero between the two wires at a distance of $3\mathrm{.}0$ cm from the first wire, what is the magnitude of the current in the second wire?

Express your answer using two significant figures.

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Part B

What is the direction of the current in the second wire?

currents flow at the same direction

currents flow opposite to each other