Which of the following sets of quantum numbers are not allowed? For each incorrect set, state why it is incorrect.
a. n = 3, ℓ = 3, mℓ = 0, ms = - 1/2
b. n = 4, ℓ = 3, mℓ = 2, ms = - 1/2
c. n = 4, ℓ = 1, mℓ = 1, ms = + 1/2
d. n = 2, ℓ = 1, mℓ = 21, ms = - 1
e. n = 5, ℓ = 24, mℓ = 2, ms = + 1/2
f. n = 3, ℓ = 1, mℓ = 2, ms = - 1/2