What is next number in the pattern below:

131 517 192 123 ?

100 prisoners are stuck in the prison in solitary cells. The warden of the prison got bored one day and offered them a challenge. He will put one prisoner per day, selected at random (a prisoner can be selected more than once), into a special room with a light bulb and a switch which controls the bulb. No other prisoners can see or control the light bulb. The prisoner in the special room can either turn on the bulb, turn off the bulb or do nothing. On any day, the prisoners can stop this process and say "Every prisoner has been in the special room at least once". If that happens to be true, all the prisoners will be set free. If it is false, then all the prisoners will be executed. The prisoners are given some time to discuss and figure out a solution. How do they ensure they all go free?

What does an Island and the letter T have in common?

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

Can you find the missing piece of the Porsche?

Give it food and it will live; give it water and it will die.

Why do people go to bed?

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

When can we add 2 to 11 and get 1 as the correct answer?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.