Facing: North
1) Q is sitting second from on the extreme ends.
(Here two cases are possible Case I Q is sitting second from the extreme North end Case II where Q is sitting second from the extreme south end)
2) Only two people are sitting between Q and
3) S is sitting seventh to the right of M.
Here Case II eliminates as Q is sitting second from the extreme end so S will not sit beyond.
4) L is sitting exactly in between Q and S.
5) Only one person is sitting between S and O.
(As O can sit both the sides of S. So, In Case I.I O is sitting second to the right of S and in Case I.II O is sitting second to the left of S.)
6) O is sitting third to the left of R.
7) R is not an immediate neighbour of S.
Here Case I.II eliminates as R is not an immediate neighbour of S.
8) P is sitting second to the left of N, who is sitting fourth to the right of R.
The final arrangement
So, N is sitting at the extreme right end of the row.