A Long Solenoid (N = 1 200 Turns/m,radius = 2 $\mu$

Multiple Choice

A long solenoid (n = 1 200 turns/m,radius = 2.0 cm) has a current of a 0.30 A in its winding.A long wire carrying a current of 20 A is parallel to and 1.0 cm from the axis of the solenoid.What is the magnitude of the resulting magnetic field at a point on the axis of the solenoid?

A) 0.60 mT
B) 0.85 mT
C) 52 $\mu$ T
D) 0.40 mT
E) 0.75 mT