Find the missing letter in the last circle logically in the given below picture.

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?

I am a white box having no key or lid.
Yet there is a golden treasure inside it.

What Am I?

What has many teeth, but cannot bite?

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

There is a brick of gold and a brick of iron in a boat (both 10-inch blocks), if they are both dropped into the water which will make the water level higher?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

John walks into the daily grocery shop and steals a $100 bill from the shop. An hour later John returns to the shop and buys some daily products for $40. John pays the owner the $100 bill and therefore the owner returns him $60.

How much money did the owner lose?

Women do it once a year after they turn 19 but men get to do it only once in a lifetime. What is it?

A Shopkeeper sold a few chickens to four different customers on a particular day. It was such that each customer purchased half of the remaining chickens and half the chicken more.

Can you find out how many chicken were sold by the shopkeeper on that day if we tell you that the fourth customer bought a single chicken ?