What number do you get when you multiply all of the numbers on a telephone's number pad?

Count The number of F's in the paragraph below:

"FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS"

A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?

You board a train. The train will have to enter a tunnel soon. You are claustrophobic. Which place is the best for you to sit?

When 99 is considered higher than 100?

Can you start the fire using two pieces of wood?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

You find yourself in a strange place guarded by two guards.One of the guard always say truth while other always lies.You don't know the identity of the two.You can ask only one question to go out from there. What should you ask?

A man is looking at a photograph of someone. His friend asks who it is. The man replies, “Brothers and sisters, I have none. But that man’s father is my father’s son.” Who was in the photograph?

What does this rebus means ?