The highlighted answer is wrong but if anyone could explain this is would be so

Most materials are not magnetic because their magnetism has worn off. their magnetic domains are arranged randomly. they lack magnetic fields. earth’s heat has destroyed their magnetism.

Adeuteron, 21h, is the nucleus of a hydrogen isotope and consists of one proton and one neutron. the plasma of deuterons in a nuclear fusion reactor must be heated to about 3.02×108 k . what is the rms speed of the deuterons? express your answer using two significant figures.

What was bohr’s contribution to the planetary model