Replace the question mark with the number below given a simple math problem.

John is found dead in a bare field. Nobody killed John,
John did not commit suicide.

Inspector Jacob found a bag just a few meters away from John which could save his life. What was in the bag?

Eight of us go fourth, not back, to protect our king from an attack. What are we?

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?

Can you identify if it's a murder or a suicide ?

Three fair coins are tossed in the air and they land with heads up. Can you calculate the chances that when they are tossed again, two coins will again land with heads up?

Spot what is wrong here in below Picture?

Can you identify the famous TV character from the rebus below?

Can you find the missing piece of the Porsche?

You have an empty wine bottle with a cork that has been secured at the top in a normal way. There is a metal ring inside the bottle that is suspended by a string.

How can you make the metal ring drop to the bottom if you are not allowed to touch anything - not the bottle, not the cork, not the thread and not the ring?