How can a man go eight days without sleep?

Here is what you have to do. You have to throw a ball as hard as you can but it must return back to you even if it does not bounce at anything. Also, you have nothing attached to the ball. There is no one on the other end to catch that ball and throw it back at you.

How will you do it?

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

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

How can you make number one disappear by adding something to it?

Do you know of a place where the wind blows south and then suddenly shifts direction towards the north?

I am an odd number. Take away a letter and I become even. What number am I?

Find the missing number in the sequence below:

What's the next in the series?

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?

Two girls were born to the same mother, on the same day, at the same time, in the same month and year and yet they're not twins. How can this be ?