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

If it is possible to make a meaningful word with the third,fifth,eighth and tenth letters of the word $DISTRIBUTE$,which of the following will be the third letter of that word? If no such word can be made,give $X$ as the answer and if more than one such word can be made,give $M$ as the answer.

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

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 letters of the given alphabet interchange positions,so that $A$ takes the place of $Z$ and $Z$ takes the place of $A$; $B$ takes the place of $Y$ and $Y$ takes the place of $B$ and so on,what will be the thirteenth letter from the right?

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 first and the second letters interchange their positions,and similarly the third and the fourth letters,the fifth and the sixth letters,and so on,which letter will be the seventeenth from your right?

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 first ten letters of the given alphabet are written in the reverse order,which of the following letters will be the seventh to the left of the twelfth letter from the right end?