John was visiting his friend Jacob. He found out that his friend's wife had just killed a burglar in self-defense.
John asks Jacob about what happened and he told that "His wife was watching television when suddenly the bell rang. She thought that it is her husband Jacob but she found the burglar who attacked her instantly and she got so frightened that she killed the burglar immediately with the knife.
John asked the police to arrest his friend's wife. Why?

Christina is practising her dance steps along with her friends. In a particular sequence, all of them form a row. At that point, Niharika is standing in the 4th position from either end of the row.
Can you find out how many girls are practising together?

How can you take 2 from 5 and leave 4?

Can you name four days which start with the letter 'T'?

I can be cracked, made, told, and played. What am I?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?