What does this below rebus puzzle mean?

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

When we see 2 but call 10?

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

There are 2 sand hourglasses.

The small one can measure 5 hours and the large one can measure 7 hours.

How can we measure 16 hours with 2 sand hourglasses running together ?

We have shown you a regular water barrel as below. Without using any measuring device can you check if the barrel is more than half-filled or less than half-filled?

Can you count the number of triangles in the given picture?

What is both possible and impossible at the same time?

How many triangles can you find in this given picture?

Lifeless eyes on my smiling face and watch your child's sleeping place. In their dreams they hold me tight. What am I?