If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

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?

Can you find the missing piece of the Porsche?

What can run but never walk, have a mouth that never speaks, have a head that never weeps, and have a bed but never sleeps?

What word begins and ends with an E, but has only one letter?

You knock a Table over in the library, and suddenly 20 eyes are looking at you.

Before Mount Everest was discovered, what was the highest mountain in the world?

There are four 3-link chains. All you have to do is join them into a big 12-link chain. For joining two closed links, one of the links must be cut and placed onto the other link for closing.

How many minimum links will you have to cut to make the big chain?

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?

I live in a bowl. I can swim. I have a tail. I also have fins and big eyes. What am I?