Seven boxes M, N, O, W, X, Y and Z are kept one over the other but not necessarily in the same order.
i. N is kept immediately above W.
ii. W and Z are kept on two different even numbered positions.
iii. There are three boxes between X and Y and two boxes between Y and
M.
iv. Y is not kept immediately below or above
M.
v. X is kept immediately above
M.
vi. O is kept immediately below
M. Which box is kept at the lowermost position?