A Long Solenoid (Diameter = 5

A long solenoid (diameter = 5.00 cm) is wound with thin wire through which a constant 0.292 A current is maintained.A wire carrying an 8.5 A current is inserted along the axis of the solenoid.The magnitude of the magnetic field at a point 5.00 mm from the axis is 0.650 mT.What are the number of turns per unit length for this solenoid?

A) 1510 turns/m
B) 1000 turns/m
C) 2000 turns/m
D) 2120 turns/m
E) 1250 turns/m