What does this rebus mean?

O
N
C
E
TIME

If in a car race, the man who came two places in front of the last man finished one ahead of the man who came fifth, how many contestants were there?

A boy purchased a book from a bookkeeper and gave him $100.
The cost of the book is $50 but the bookkeeper has no change, so he gets the change from the next shop and returns the boy his $50.

After some time the next shopkeeper came with the $100 note and told the bookkeeper that the note was a fraud, so he took the money back.

How much loss did the bookkeeper face?

Can you count the number of squares in the figure below?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

A tourist visits a small town for his research. While in the town, he decides to get a haircut. Since the town is quite small, there are only two barbers in the town � one on the North Street and one on the South Street. The barbershop on the North Street is a mess and the barber has a weird and pathetic haircut. While the barbershop at the South Street is pretty tidy and the barber as well has an impressive haircut.

Which barbershop will the tourist visit for his haircut and why?

Can you decipher the following common phrase?

T M C
A U O
H S M
W T E

Name a key which is hardest to turn.

A B C D E F G H

These are the letters given to you. Now you have to find out the letter that comes two to the right of the letter which is immediately to the left of the letter that comes three to the right of the letter that comes midway between the letter two to the left of the letter C and the letter immediately to the right of the letter F.

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?