What has hands, but can’t clap?

What is the last thing you take off before bed?

A woman lives in a skyscraper thirty-six floors high and is served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

Can you count the number of quadrilaterals in the picture below?

Which is faster, Heat or Cold ? Explain.

What is the below Rebus indicate?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

There are hundred red gems and hundred blue gems. The blue gems are priceless while the red gems equal wastage. You have two sacks one labeled Heads and the other Tails. You have to distribute the gems as you want in the two sacks. Then a coin will be flipped and you will be asked to pick up a gem randomly from the corresponding sacks.

How will you distribute the gems between the sacks so that the odds of picking a Blue gem are maximum?

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?

Name a key which is hardest to turn.