Answer:
Step-by-step explanation:
The wires are in circular shape . They have common center .
magnetic field due to circular wire is given by the formula
B =

where I is current , r is radius of the coil .
magnetic field due to inner wire
=

magnetic field due to outer wire
=

These should be equal and opposite so that by cancelling each other , they create zero field.
=

I = 16.66 A
Direction of current should be in opposite direction ie anticlockwise when looking from above.