What brings you down but never up?

On a certain day, John celebrated his birthday. Two days later, his older twin brother Jacob celebrated his birthday.

Is this even possible? How can it be?

Find the Goldfish below the given Image.

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?

What does this rebus mean?

O
N
C
E
TIME

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C

What is the riddle which can be asked all day with a different correct answer each time.

A little girl goes to the store and buys one dozen eggs. As she is going home, all but three break. How many eggs are left unbroken?

Why Aeroplane windows are round?