If it is possible to make a meaningful word with the fourth,the seventh,the eleventh and the thirteenth letters of the word $CATEGORISATION$,which of the following will be the first letter of that word? If no such word can be made,give $X$ as the answer. If more than one such word can be made,give $M$ as the answer.

How many pairs of letters in the word $CATASTROPHE$ have as many letters between them in the word as 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.
$E, O, C, D, L, I$
$1, 2, 3, 4, 5, 6$

If the first and third letters in the word $NECESSARY$ were interchanged,also the fourth and the sixth letters,and the seventh and the ninth letters,which of the following would be the seventh letter from the left?

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

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?