What goes up but never comes down?

You knock a Table over in the library, and suddenly 20 eyes are looking at you.

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

Astrology starts with the alphabet A, Biology starts with B, Psychology with P and Limnology with L.

Can you find an "ology" that begins with a P?

There are nine dots in the picture that has been attached with this question. Can you join all the dots by drawing four straight lines without picking up your pen?

No one wants to have it, but if one got it, he does not want to lose it. What is It?

Find the number of squares in the below-given picture.

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different.

How do you measure 45 minutes?

What is the probability of choosing the correct answer at random from the options below?

a) 1/4
b) 1/2
c) 1
d) 1/4

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?