Count the squares in the matchstick puzzle below?

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

What has one eye, but can’t see?

Double it and multiply it by 4. Then divide it by 8 and you’ll have it once more. What number is it?

I have thought of a number that is made up by using all the ten digits just once. Here are a few clues for you to guess my number:

First digits is divisible by 1.
First two digits are divisible by 2.
First three digits are divisible by 3.
First four digits are divisible by 4.
First five digits are divisible by 5.
First six digits are divisible by 6.
First seven digits are divisible by 7.
First eight digits are divisible by 8.
First nine digits are divisible by 9.
The number is divisible by 10.

Can you find out the number ?

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

What famous saying does this rebus mean?

COME SERVED <---
COME SERVED
COME SERVED
COME SERVED
COME SERVED

In the Thar desert, 3 men found a big 24L Jar is full of water. Since there is a shortage of water so they decided to distribute the water among themselves such that they all have equal amounts of it. But they only have a 13L, a 5L and an 11-litre Jar.

How do they do it?

I’m tall when I’m young, and I’m short when I’m old. What am I?

There was an aeroplane crash, every single person died, but two people survived. How is this possible?