The magnetic vector M is the vector sum of the magnetic moments of all the atoms contained in a unit volume (1m3). If a certain type of iron with 8.5 ×1028 atoms/m3 contributes one electron per atom to align its spin magnetic moment along the direction of the applied field, find
(a) The spin magnetic moment of a single electron, given that me = 9.1 ×10-31 (kg) and h = 1.06 ×10-34 (J.s), and
(b) The magnitude of M.