Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

Here is a conversation between a couple who both are software professionals.

Husband: Hey! What is your date of birth?
Wife Replied Angrily: It is 591062400
Husband after doing some calculations replied, "Got It".

What is the DOB of the wife?

Consider all the numbers between 1 and 1 million. Among all these numbers, there is something very special about the number 8 and the number 2202. What is it?

You board a train. The train will have to enter a tunnel soon. You are claustrophobic. Which place is the best for you to sit?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

I add 5 to 9 and get 2. The answer is correct, so what am I?

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?