In each of the following questions, certain pairs of words are given, out of which the words in all pairs excepts one, bear a certain common relationship. Choose the pair in which the words are differently related?

Find the missing (?) in the series.
NA, PC, RE, TG, ?, XK, ZM

If A=1 and ANT=105, then ASK=?

Given below is a question followed by two statements I and II. Read both statements carefully to decide which one of them is sufficient to answer the question.
 Six people - A, B, C, D, E and F are sitting in a straight line facing north. Who sits to the immediate left of D?

(1) A sits second from one of the extreme ends of the line. Only two people sit between A and B. E sits to the immediate right of C.
(II) C sits third from the left end of the line. Only one person sits between C and F. E sits third to the right of F.

The series given below contains a sequence of numbers. Identify the incorrect combination: 

56, 54, 58, 49, 66, 34

Complete the series choosing the missing letter

__ aaba __ aa__ __aa

In each of the following questions, five words are given. Which of them will come in the middle if all of them are arranged alphabetically as in a dictionary?

From the given alternative words, select the one which cannot be formed by using the letters of the given word.
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