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

What does the following BrainBat signifies?

ABCDEFGHIJKLMNOPQRSTUVWYZ

QQQQQQQQQQQQQQQQQQQQQQQQQ.

what does this picture(rebus) riddle means ?

You have an empty wine bottle with a cork that has been secured at the top in a normal way. There is a metal ring inside the bottle that is suspended by a string.

How can you make the metal ring drop to the bottom if you are not allowed to touch anything - not the bottle, not the cork, not the thread and not the ring?

You can see it everyday, But cannot touch it at will. What is it?

I cry without having a voice.
I fly without having wings.
I bite without having teeth.
I whisper without a mouth.

Who am I?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

This was asked in an interview with Coa-Cola.

The interviewer has given me 100 marbles(50 white and 50 black) and two empty boxes.
He then told me that he will leave the room and i need to place all the marbles in two boxes.

And When he come back, he will draw a marble from any of the two box and if the marble is white I will be hired.

Also
* No box can be empty.
* All 100 marbles must be placed in one of the two boxes.

So what should I have done?

What is represented by this rebus?

once
time