If a copper rod carries a direct current, the magnetic field associated with the current will be_________

If a long copper rod carries a direct current, the magnetic field associated with the current will be

If a long hollow copper pipe carriers a direct current, the magnetic field associated with the current will be:

If a long hollow copper pipe carriers a direct current, the magnetic field associated with the current will be:

If a long hollow copper pipe carriers a direct current, the magnetic field associated with the current will be:

If a long hollow copper pipe carriers a direct current, the magnetic field associated with the current will be:

IF a copper rod carries a direct current,then where will the magnetic field in the conductor?