Verbal Reasoning - Mental Ability Questions

Prem starts to school from his house and walks 400 metres towards north, turns left and walks 100 metres, turns left and walks 200 metres, turns left and walks 100 metres. How far he is away from his house?

While posing for a family photo, the father is standing to the right of the son and left of the grandmother. The mother is sitting to the left of her daughter and right of the grandmother. Who is seated in the middle?

Select the related word/letters/numbers from the given alternatives:
3 : 243 :: 5 : ?

Select the related word/letters/numbers from the given alternatives: DBCE : QOPR :: JLKI : ?

P is the brother of Q. Q is the brother of R. P is the son of S. Based these three statements, much of the following statements cannot be definitely true?

In a certain code language, '+' represents 'x', '-' represents '+', 'x' represents '÷' and '÷' represents '-'. What is the answer to the following question?

45 x 5 + 2 - 20 = ?

In each of the following questions three statements are given and these statements are followed by two conclusions numbered (1) and (2). You have to take the given three statements to be true even if they seem to be at variance from commonly known facts. Read the conclusions and then decide which of the given conclusions logically follows from the two given statements, disregarding commonly known facts.
Statements:

All books are novels.
No novel is a magazine.
All magazines are newspaper.
Conclusions: 

I.No book is a magazine.
II. Some newspaper are novels.

Ram said , "Sita is my paternal great grandfather's only son's only daughter-in-law". How is Sita related to Ram?