Find the next number in the sequence

1, 2, 6, 21, 88, __?

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?

how come the second man dies?

John gave half of the apples he had plus one more to Jacob. He gave half of the remaining ones plus one more to James. Now, John was left with just one apple.

Can you find out how many did he have in the beginning?

The more it dries, the wetter it becomes. Can you tell what it is?

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different. How do you measure 45 minutes?

Steffi's daughter Jazelle needs to be picked up from school every day.
Steffi asks one of her colleagues to pick up Jazelle from the school. Steffi devised a password system to confirm that Jazelle goes with the correct colleague only.

The password on Monday was SJM16.
The password on Wednesday was TAW39.

What will the password be for Friday?

That attorney is my brother, testified the accountant.

But the attorney testified he didn't have a brother.

Who is lying?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

A boy and his father are caught in a traffic accident, and the father dies. Immediately the boy is rushed to a hospital, suffering from injuries. But the attending surgeon at the hospital, upon seeing the boy, says 'I cannot operate. This boy is my son.' How is this situation explained?