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?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

Krish is 45 years old and his mother Crishtina is 73 years old.

Can you find out how many years ago, his mother was three times his age?

What has one eye, but can’t see?

I can turn polar bears white.
I can make anyone dance.
I can make everyone cry
I can make your hands clap
I can make you thin.
I can make you smile.
I can make you smile

Can you guess the riddle?

What does it mean?

who is silent in the parliament?

No matter how little or how much you use me, you change me every month. What am I?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?