The electrons identified by quantum numbers n and l (i) n = 4, l = 1 (ii) n = 4, l = 0 (iii)  n =3, l = 2 (iv) n = 3, l = 1 can be placed in order of increasing energy, from lowest to highest as

Energy of n=3,l=1 < n=4,l=0 <  n=3.l=2 <  n=4,l=1n+l                  (3+1)        (4+0)        (3+2)           (4+1)n = 3, l = 1 has lesser 'n' value than n = 4, l = 0n = 3, l = 2 has lesser 'n' value than n = 4, l = 1