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

People put me on the table and cut me but do not eat me. What am I?

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?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

Can you replace the question mark with the correct number in the below table sequence?

A wealthy man lives alone in a small cottage. Being partially handicapped he had everything delivered to his cottage. The mailman was delivering a letter one Thursday when he noticed that the front door was ajar. Through the opening he could see the man's body lying in a pool of dried blood. When a police officer arrived he surveyed the scene. On the porch were two bottles of warm milk, Monday's newspaper, a catalog, flyers, and unopened mail. The police officer suspects it was foul play. Who does he suspect and why?

Three men in a cafe order a meal the total cost of which is $15. They each contribute $5. The waiter takes the money to the chef who recognises the three as friends and asks the waiter to return $5 to the men.

The waiter is not only poor at mathematics but dishonest and instead of going to the trouble of splitting the $5 between the three he simply gives them $1 each and pockets the remaining $2 for himself.

Now, each of the men effectively paid $4, the total paid is therefore $12. Add the $2 in the waiters pocket and this comes to $14. Where has the other $1 gone from the original $15?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

Who has married many women but was never married?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?