2, 3, 5, 9, 17, _ What is the next number in the sequence?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

There is so small cabin inside a deep forest.
All the forest burned out to worst possible but the inside of the cabin is still the same.
However all the person inside the cabin die.

How come ?

What is always in front of you but can’t be seen?

In a stable, there are men and horses. In all, there are 22 heads and 72 feet. How many men and how many horses are in the stable

John is the son of Jacob.
So,
Jacob is the_____of John's father?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

Can you make numbers like 24, using numbers 3,3,7 & 7 with any arithmetic operator?

Assume the given figure to be a delicious doughnut. Yes, now you can concentrate more on the puzzle. So you have this delicious doughnut in your refrigerator when your friends come knocking at the door. There are eight of them. Now you have to make three cuts in this doughnut so that each one of you nine people can enjoy a piece of it. Neither you nor your friends would mind the size of their piece as long as they are getting it. How will you do it?

Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?