What is both possible and impossible at the same time?

Only Highly Attentive Can Spot The Ladder In This Library In 7 Seconds! Can You?

No matter how little or how much you use me, you change me every month. What am I?

It can be easily calculated that the digits 0 to 9 can be arranged into 3628800 distinct ten-digit numbers.

But do you know how many of these numbers are prime?

Why is the longest human nose just 11 inches?

1 rabbit saw 9 elephants while going to the river. Every elephant saw 3 monkeys going toward the river. Each monkey had 1 parrot in each hand. How many animals are going towards the river?

Can you replace the question mark with the correct number in the below table sequence?

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

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 is the centre of gravity?