Buy me, smell me or deliver me, I do not change.

Who am I?

What Time Should the last watch show in the below figure?

Why do people go to bed?

The horse jumps over the king.
Strangely there is absolutely no scratch on him.

Can anyone explain, how is this possible?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

What is the largest number you can write with just 3 digits?

You are stuck on an island where you have nothing. You find four pieces of paper somewhere on the island. What will be your strategy to escape from the island safely?

PS: No other resource is available to you on the island, neither can you build anything.

A bomb goes off.
Carnage.
One person, only a few feet away, survives! How can this be?

What do you get if you add 2 to 100 four times?

The host of a game show, offers the guest a choice of three doors. Behind one is a expensive car, but behind the other two are goats.
After you have chosen one door, he reveals one of the other two doors behind which is a goat (he wouldn't reveal a car).

Now he gives you the chance to switch to the other unrevealed door or stay at your initial choice. You will then get what is behind that door.

You cannot hear the goats from behind the doors, or in any way know which door has the prize.

Should you stay, or switch, or doesn't it matter?