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?

I am a type of vehicle that has two wheels and is powered by humans. What am I?
Hint 1: You can ride me for exercise.
Hint 2: I am environment-friendly.

Assume the given figure to be a delicious doughnut. Yes, now you can concentrate more on the puzzle. So you have this delicious doughnut in your refrigerator when your friends come knocking at the door. There are eight of them. Now you have to make three cuts in this doughnut so that each one of you nine people can enjoy a piece of it. Neither you nor your friends would mind the size of their piece as long as they are getting it. How will you do it?

There was a kingdom in which the king had no heir to take over his thrown. Even the queen was dead and he himself was on the verge of dying. He thought about it and then summoned all of the teenagers. He gave one seed each to all of them and asked them to grow the plant. He announced that the one with the most beautiful plant will become the king/queen of the empire after the death of the king.

After a month, all of them were called. The king looked at all of the plants but announced the girl with an empty pot as the queen of the empire. Why?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

Out of three Friends John, Jacob and Jonny one of them is a king, one is a bureaucrat, and one is a Spy.

The king always tells the truth, the bureaucrat always lies, and the Spy can either lie or tell the truth.

John says: Jonny is a bureaucrat
Jacob says: John is a king
Jonny says: I am a Spy

Tell me, Who is the king, who is the bureaucrat, and who is the Spy?

In the four images below, can you find the odd one out?

I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I?

Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

Find three numbers such that

* When we multiply three numbers, we will get the prime numbers.
* The difference between the second and the first number is equal to the third and second.