Find the Next Number in the Sequence

2 9 3 1 8 4 3 6 5 7 ?

What is the centre of gravity?

Can you solve the photo plexer logic ?

Four children having five rocks each were playing a game in which they had to throw the rock at a particular solid area in the water. Child 1- Succeeded in throwing three rocks at a solid area but one of the rocks sunk. Child 3 - His aim was so bad that all rocks got sunk. Child 4- He was awesome and none of the rocks got sunk. Child 2 - Was the winner but was struck by a rock in the head and died. Who killed Child 2?

I had an infinite supply of water and 5 litres and 3 litres jars.

How would you measure exactly 4 litres in the least number of steps?

Can you decipher the below rebus?

PBLUESAISNUERSES

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

Can you count the number of seconds in a year?

Clue: You need to bother about calculation.

French Police inspects a room where there are no windows, no doors, no tables and is almost empty expect there is just a puddle of water. They found a dead man who obviously hung herself from the ceiling, but they are not able to figure out how this had happened.

John and Jacob entered the crime scene and easily able to solve the case.

How did the man die?

How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?