Can you replace the question mark with the correct number in the below table sequence?

When we see 2 but call 10?

I am white when I am dirty, and black when I am clean. What am I?

A large water tank has two inlet pipes (a large one and a small one) and one outlet pipe. It takes 3 hours to fill the tank with the large inlet pipe. On the other hand, it takes 6 hours to fill the tank with the small inlet pipe. The outlet pipe allows the full tank to be emptied in 9 hours.

What fraction of the tank (initially empty) will be filled in 0.64 hours if all three pipes are in operation? Give your answer to two decimal places (e.g., 0.25, 0.5, or 0.75).

It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
What is it?

Paul's height is six feet, he's an assistant at a butcher's shop and wears size 9 shoes. What does he weigh?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

Decode below rebus
D
N
A
T
S , D

1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10

Look at the picture and find out which square is not linked with any of the other squares.