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

Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

Who has married many women but was never married?

What is the last thing you take off before bed?

When I asked a girl's name she told me her name is the date '07/09/2001'.

I thought for a few seconds and then I got her name. Do you?

I have a five and a three-gallon jar. Assuming there is an infinite supply of water, how can I measure one-gallon water?

What is the centre of gravity?

I am a type of food that is often found in the fridge and can be white in colour. What I am?
Hint 1: I am a dairy product.
Hint 2: You can spread me on the bread.

There was a minor accident with a doctor's son but the doctor noticed no major injury. After the treatment, the father of that doctors son is sitting with the son of the doctor without the doctor being in the room.

How can this be possible?

How can you write nineteen in a manner that if we take out one, it becomes twenty?