What is the longest word in the dictionary?

Who is that with a neck and no head, two arms and no hands? What is it?

When it is alive we sing, when it is dead we clap our hands. What is it?

The more of this there is, the less you see. What is it?

I am something people love or hate. I change peoples appearances and thoughts. If a person takes care of them self I will go up even higher. To some people I will fool them. To others I am a mystery. Some people might want to try and hide me but I will show. No matter how hard people try I will Never go down. What am I?

What 8 letter word can have a letter taken away and it still makes a word. Take another letter away and it still makes a word. Keep on doing that until you have one letter left. What is the word?

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?

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

Prove that the below maths equation is true.

8 + 8 = 91

I am a prime number.
The double of myself is equal to the square of me.

which number am I?