Solution:

Valar Dohaeris

Explanation:
"Valar Dohaeris" is a phrase commonly used in Braavos, means "all men must die".
The common response of "Valar Dohaeris" is "Valar Dohaeris" means "all men must serve."

Solution:

she cant find 11 on phone.

Solution:

Simple, the slow ones are in prison :-)

Solution:

It is mentioned that 'all but fifteen pencils' were used by him. This phrase means that except fifteen, all his pencils were used.

Thus, he is left with fifteen pencils.

Solution:

No

Solution:

The question tells us that a taxi driver was going the wrong way. It is however not mentioned that he was driving the cab. As per the question, it is evident that he was on foot and that is why the police officer did not fine him.

Solution:

He cannot marry his widow's sister in any country. This is because if his wife is a widow, he is already dead.

Solution:

Mayank took birth on Sunday.

Mayank was born 25 days before Rohit and thus the birth date of Mayank will be 8 Feb 1970.
Republic Day fell on Monday.
Number of days if counted from 26 January to 8 February will be 13.

After 13 days of Monday, it will be Sunday.

Solution:

Yes, this can be possible if the match was between two female boxers.

Solution:

Diwali was celebrated as a mark of Lord Krishna win over the Narakasuna by killing him. Now Krishnavathaar comes after Raamavathaar in the Dasavataar. Therefore, Lord Rama could not have celebrated Diwali.