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

You throw me out when you want to use me and you take me in when you don't want to use me.

Who Am I?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

Can you spot what's wrong with the following sentence?

PETER WAS ANGRY AT
HIMSELF BECAUSE HE
ACCIDENTALLY LEFT THE
THE KEYS TO HIS CAR
AT HIS FRIEND'S HOUSE.

Known by all without exception, Forever here, for your protection, Sometimes strong, sometimes weak, Right after the night I come - hot and chic. And while millions of miles away, I always get to you, I find my way. No life around could do without me, Can you guess what I might be?

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?

In an interview, a boy was asked an unusual question 'How two persons sitting with a table in between them can't see each other?' He was unable to reply. Can you?

My first is in chocolate but not in ham. My second is in cake and also in jam. My third at tea time is easily found. Altogether, this is a friend who is often around. What is it?

Samuel was out for a walk when it started to rain. He did not have an umbrella and he wasn't wearing a hat. His clothes were soaked, yet not a single hair on his head got wet. How could this happen?

There are five vowels (a, e, i, o, u) in the English language.
Can you tell us a word that contains all these vowels?