If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

On a special event at the prison, 5 prisoners John, Jacob, Krist, Tang, and Dang given a chance to go to a sauna and can bring one thing with them.

Following are the things that the prisoners bring with them.
John: A soda
Jacob: Thermos
Krist: Book named "How to kill"
Tang: A Walkman
Dang: Harmonica

Since it is a Sauna, no one can see each other. After a while When the steam is switched, Tang was found dead and there was blood all around.
J Bond was called and he instantly come to know who can be the murderer. How?

Why is 6 afraid of 7?

Can you find out the missing number in the grid?

I have feet, but no legs. Which animal Am I?

Can you place six X (crosses) in below board without making three in a row in any way ?

Consider this about a word: The first two letters signify a male, the first three letters signify a female, the first four letters signify a great, while the entire world signifies a great woman. What is the word?

Can you solve this picture maths equation?

You are stuck on an island where you have nothing. You find four pieces of paper somewhere on the island. What will be your strategy to escape from the island safely?

PS: No other resource is available to you on the island, neither can you build anything.

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?