What will come in place of the question mark $(?)$ in the following letter-group series based on the English alphabet?
$WC, RE, NI, KO, ?$

If it is possible to make a meaningful word from the second,the third,the tenth,and the eleventh letters of the word $PASSIONATELY$ using each letter only once,the second letter of that word is your answer. If no such word can be formed,your answer is $X$,and if more than one word can be formed,your answer is $Y$.

How many pairs of letters in the word $CHAIRS$ have as many letters between them in the word as in the alphabet?

Arrange the given words in alphabetical order and choose the one that comes in the middle.

$A$ group of letters is given which are numbered $1, 2, 3, 4, 5$ and $6$. Below are given four alternatives containing combinations of these numbers. Select the combination of numbers so that the letters arranged accordingly form a meaningful word.
$E, H, N, T, O, R$
$1, 2, 3, 4, 5, 6$

If all the letters in the word $MERCIFUL$ are rearranged in alphabetical order and substituted by the alphabet preceding them in the English alphabet,what will be the new arrangement of letters?