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

Three friends decide to distribute the soda cans they had among them. When all of them had drunk four cans each, the total number of cans that remained was equal to the cans each one of them had after they had divided the cans.

Can you calculate the total number of cans before distribution?

What happened when the wheel was invented?

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

My cousin lives in one story house in Antarctica. His house is made the of-of sandstone. what is the color of stairs?

What is the next number in this matchsticks series riddle?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

The pound is not a finish.

We are sharing a few instructions below, which you have to use in any suitable order to modify the above sentence such that the end sentence is a scientific fact.

- Eliminate a letter and supplement another in its place.
- Take away one word.
- Remove one letter from one word.
- Get rid of two letters from one word.
- Swap a word with its antonym.

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

There was a kingdom in which the king had no heir to take over his thrown. Even the queen was dead and he himself was on the verge of dying. He thought about it and then summoned all of the teenagers. He gave one seed each to all of them and asked them to grow the plant. He announced that the one with the most beautiful plant will become the king/queen of the empire after the death of the king.

After a month, all of them were called. The king looked at all of the plants but announced the girl with an empty pot as the queen of the empire. Why?