Consider the cross-sectional view of two, infinitely long, conductors shown below. The top conductor, located at =4
z
=
4
=4
z
=
4
has a current density of
⃗1=^4A/m2
J
→
1
=
a
x
^
4
A/m
2
⃗1=^4A/m2
J
→
1
=
a
x
^
4
A/m
2
and a radius of 1m. The lower conductor, located at
=−4
z
=
−
4
=−4
z
=
−
4
, has a current density of
⃗2=−^16A/m2
J
→
2
=
−
a
x
^
16
A/m
2
⃗2=−^16A/m2
J
→
2
=
−
a
x
^
16
A/m
2
and a radius of 0.5m.

What is the magnitude and direction of the magnetic field at (0, 0, 0)?