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

If a meaningful word can be formed by rearranging the letters $USCALA$,the first letter of the word so formed is the answer. If no such word can be formed,the answer is $X$.

Select the combination of numbers so that letters arranged accordingly will form a meaningful word.
$V, A, R, S, T, E$
$1, 2, 3, 4, 5, 6$

Arrange the given words in alphabetical order and choose the one that comes in the second place:

Each of the following questions is based on the following alphabet series.
$A, B, C, D, E, F, G, H, I, J, K, L, M$
$N, O, P, Q, R, S, T, U, V, W, X, Y, Z$
If the above alphabet is written in the reverse order,which will be the eighth letter to the right of $O$?

How many such pairs of letters are there in the word $DOCUMENT$,each of which has as many letters between them in the word as in the English alphabet?