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

I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?

That attorney is my brother, testified the accountant.

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

Who is lying?

Can you find the largest Three-digit number whose sum is 14 and whose square is less than 5,00,000?

Can you find out a way through which you can make five squares out of the given figure by moving just six match sticks?

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?

He does not have any heart but still, He manages to live.
If you kill him, you will eventually die but yet you kill him.
He cannot run, who is He?

A professor thinks of two consecutive numbers between 1 and 10.
'A' knows the 1st number and 'B' knows the second number

A: I do not know your number.
B: Nor do I know your number.
A: Now I know.

What are the four solutions for this?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

What is the next number?

77, 49, 36, 18 ?