The electrons identified by quantum numbers n and l :
a) n = 5, l = 1
(b) n = 5, l = 0
(c) n = 4, l = 2
(d) n = 4, l = 1
can be placed in order of increasing energy as :
1
c) < (d) < (b) < (a)
2
(d) < (b) < (c) < (a)
3
(b) < (d) < (a) < (c)
4
(a) < (c) < (b) < (d)