Verbal Reasoning - Mental Ability Questions

In the following question, from the given alternative words, select the word which cannot be formed using the letters of the given word.
Nightwalker

Select the missing number from the given options?

A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.
DE, GI, KN, ?

A series is given with one term missing. Choose the correct alternative from the given ones that will complete the series.

DW, FY, HA, JC, ?

Select the missing numbers from the given alternatives.

A and B start from the same point. A cycles 10 km South, then turns to her right and cycles 9 km. B cycles 2 km North, then turns West and cycles 15 km, then turns to her left and cycles 12 km. Where is B with respect to A now?

In the given diagram, Set U is the universal set and Set L, M and N represent students studying History, Geography and Language, respectively.

What is the total number o students studying History and Geography but NOT Language?

A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.

RMT, PKR, NIP, ?, JEL