I am five letter word that is under you.
If you remove my 1st letter, then I am over you.
If you remove my 1st and 2nd letters then I am all around you.

Who am I?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

You order chicken wings at KFC in the boxes of 6, 9 and 20. What is the largest number of wings that you cannot obtain by buying in any combination of the boxes?

What's the only room from which no one can enter or leave

Can you decipher these quotes by Albert Einstein?
Blf xzm mvevi hloev z kilyovn lm gsv ovevo lm dsrxs rg dzh xivzgvw.

On the dull night when the blonde was dozing, she heard an odd clamour and she saw that there was a bizarre man with a gun simply outside her home. So she raced to the telephone to call the police, however, she can't dial 911. Why?

What am I?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

A blonde put eyeliner on her head. Why?

I am a normal creature, but I have five hands. I can even have more but even then I will be considered normal.

Who am I?