Select all of the following which are possible sets of quantum
numbers (n, ℓ, mℓ,
ms) for the 3 electrons in the unfilled shell
of the ground state of a nitrogen atom.
(2, 1, -1, -1/2), (2, 1, 0, 1/2), (2, 1, 1, -1/2)
(2, -1, 1, 1/2), (2, -1, 0, 1/2), (2, -1, -1, 1/2)
(2, 1, 1, 1/2), (2, 1, 0, 1/2), (2, 1, -1, 1/2)
(2, 1, -1, 1/2), (2, 1, 0, 1/2), (2, 1, 1, 1/2)