Identify the hidden meaning behind this picture?

What work can one never finish?

In my garden, I have many trees but only one of them is the mango tree. In these mango trees, there are some mangoes(as expected).

But after a strong wind, there are neither mangoes on the tree nor on the ground. Explain?

Christina is older than Kareena and Karishma. Katrina is older than Karishma and younger than Kareena. If Kareena has a brother named John, who is older than Christina, who's the youngest?

What is black when you buy it, red when you use it, and gray when you throw it away?

Only one colour, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

Jigsaw captured 100 people and make them stand in a circle and all these people are labelled as Person1, Person2, Person3... Person100. He made them play a crazy game in which Person 1 shot Person 2 and pass the gun to the next person and so on until one stands alive.

Which person will survive in the end?

A B C D E F G H

These are the letters given to you. Now you have to find out the letter that comes two to the right of the letter which is immediately to the left of the letter that comes three to the right of the letter that comes midway between the letter two to the left of the letter C and the letter immediately to the right of the letter F.

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?