Two infinitely long parallel wires carry current `I_(1) = 8A` and `I_(2) = 10` A in opposite directions. The separation between the wires is `d = 0.12` m. Find the magnitude of magnetic field at a point P that is at a perpendicular distance `r_(1) = 0.16` m and `r_(2) = 0.20` m respectively from the wires.