I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?

In the picture that is attached with this question, you can find a square which comprises of four little squares inside it. Consider this square to be made with matchsticks. You have to remove two matchsticks such that only two squares remain instead of five.How will you do it ?

I noticed one of the words in the oxford dictionary is spelled incorrectly. What about you?

A detective visits his friend John just to discover that John's neighbour Dr Jacob was murdered. Dr Jacob, who is a mathematician wrote the murderer's name in a code word "Hcqtfz". There were five suspects
1. Ajit
2. Pankaj
3. Ganpat
4. Deenu
5. Hariya

The Detective was instantly able to find the murderer.
Can you?

Why is 6 afraid of 7?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

John is the son of Jacob.
So,
Jacob is the_____of John's father?

Find The Next Number in this series.
1, 2, 6, 42, 1806 ?

Using four sevens (7) and a one (1) create the number 100. Except for the five numerals, you can use the usual mathematical operations (+, -, x, :), root and brackets ()