What is the coolest letter in the alphabet?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

The dirtier I get, the whiter I look. Who am I?

John is selling fruits.
He sells grapes at $30, Dates $25, and a Wolfberry $45.
At what price does he sell fig?

PS: Logical Thinking

If you say my name, I will no longer exist. What am I?

What word is represented by this rebus?

Below is the sum of symbols in each row and column in the figure. Analyzing the figure, can you find out the value of the symbols?

In order to complete the racing competition, the Mexico racetrack has to submit its top and the most famous three horses to win the competition. Due to an electrical storm, all the records are cleared and no one knows which horse holds the record. They all look identical and it becomes even more difficult to differentiate the horses. There are 25 horses in the Mexico racetrack. But there can be only five horses at a time on the track. What will the least number of races that can be conducted to find out the three fastest horses?

What came first, the chicken or the egg?

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?