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

Christina, Allison and Lena are 3 daughters of John a well-known Mathematician, When I asked John the age of their daughters. He replied "The current age of her daughters is prime. Also, the difference between their ages is also prime."

How old are the daughters?

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?

A Miser man decided to go on a vacation for a month. He goes to the bank and asks for a trip loan of $500. The bank officer asks the man that the loan can only be approved when he mortgage some valuable thing at the bank. Miser man mortgages his only car whose worth was a whopping $80000. The Bank officer laughed at him and approve the loan instantly. After vacation when the miser man returns, the bank officer asked him "Are you an idiot, why is your mortgage such an expensive car for such a short loan?".

Miser man replied with some reason and the bank officer agreed that the miser man is actually not an idiot.

What did miser man reply to the bank loan officer?.

The more it dries, the wetter it becomes. Can you tell what it is?

There are three boxes on a table. One of the box contains Gold and the other two are empty. A printed message contains in each box. One of the message is true and the other two are lies.

The first box says "The Gold is not here".

The Second box says "The Gold is not here".

The Third box says "The Gold is in the Second box".

Which box has the Gold?

A man is found dead with a knife in his back When the investigation is done. A chair lays beside him and the forensic team finds moisture around the body.

If he committed suicide, how did he do it?

Can you name some countries which do not have the alphabet 'A' in them?

John is looking at Jenifer, but Jenifer is looking at Jacob. John is married, but Jacob is not.

Is a married person looking at an unmarried person ?

It begins where the time ends.
Its second is an expression of surprise.
Its third is a question.
Its fourth is urinate.
It ends with a drink.

Which country it is?