A current of 45 A is passing through an infinitely long wire which lies along the axis of an infinitely long solenoid of radius 1 cm. The magnetic field by the solenoid in the direction of the current in the wire is 4 mT. What is the approximate magnitude of the resultant magnetic field at a point 3 mm radially away from the solenoid axis?
A.5mT
B.1mT
C.7mT
D.3mT
