How many pairs of letters are there in the word $SEQUENTIAL$ which have as many letters between them as are in the alphabet?

$A$ 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 that combination of numbers so that the letters arranged accordingly form a meaningful word.
$T, L, P, N, A, E$
$1, 2, 3, 4, 5, 6$

How many pairs of letters are there in the word $CLANGOUR$ which have as many letters between them in the word as in the alphabet?

Find which one word cannot be made from the letters of the given word.
$COMMENTATOR$

In the following list of letters,how many $O$'s are followed by $Q$'s but not preceded by $D$'s?
$D, O, Q, O, D, Q, O, D, O, D, Q, D, O, Q, D, S, D, Q, P$
$O, Q, D, S, S, S, D, O, Q, O, Q, D, O, Q, D, D, O, Q$

$A$ 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.
$N, A, E, H, L, D$
$1, 2, 3, 4, 5, 6$