In the se unit of
klich of the following
density​

This question is incomplete and not physics but i'm  willing to if you can give a better question

Aand b antarctica is a north pole.  field lines enter earth near the north pole.the magnetic pole near antarctica is a north pole.compasses point toward a magnetic pole that is a north pole.field lines circle earth from east to west.a compass can lead a hiker to the geographic north pole.

Blue light reflected from the ball enters human eyes.