Who can jump higher than a Mountain?

Find out the missing number in the picture attached:

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C

In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

A man desired to get into his work building, however he had forgotten his code.
However, he did recollect five pieces of information
* Fifth number + Third number = 14
* The fourth number is one more than the second number.
* The first number is one less than twice the second number.
* The second number and the third number equals 10.
* The sum of all five numbers is 30.

What is the code ?

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

A girl has as many brothers as sisters, but each brother has only half as many brothers as sisters. How many brothers and sisters are there in the family?

What numbers should go on the bottom line?
3 6 9 15
8 2 10 12
11 8 19 27
19 10 29 39
? ? ? ?

How can a man go eight days without sleep?

There are five vowels (a, e, i, o, u) in the English language.
Can you tell us a word that contains all these vowels?