Gallium's last electron is 4P1 which means "n" or the principal quantum number is equal to 4.
"l" which type of orbital, (S=0, P=1, D=2, F=3) from 4p1 is equal to 1.
"ml" which P, [ (1st) = -1, (2nd) = 0, (3rd) = +1] is equal to -1"ms"can be both -1/2 and +1/2 but the first electron is associated with +1/2