Which number should replace the question mark?

Who has married many women but was never married?

A man has to get a fox, a chicken, and a sack of corn across a river.

He has a rowboat, and it can only carry him and one other thing.
If the fox and the chicken are left together, the fox will eat the chicken.
If the chicken and the corn are left together, the chicken will eat the corn.

How does the man do it?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

What question can you never answer yes to?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

What can go through glass without breaking it?

Can you name an animal whose killing cannot be performed without spilling your own blood?

Can you find the 09 errors in the picture below?

What has 88 keys?