$\begin{array}{1 1} a)n = 4, l = 0, m = 0, s = + 1/2 \\ b) n = 3, l = 1, m = 1, s = - 1/2 \\ c) n = 3, l = 2, m = 1, s = - 1/2 \\ d) n = 3, l = 0, m = 0, s = + 1/2 \end{array} $