Can you find a five letter word that is left with only two letters if one is removed?

John was so frustrated to be the suspect of being a sleeper terrorist that he shoot himself right between the eyes with a revolver in his toilet. The revolver and the bullets were accurate. Minutes later John walks out of the toilet unharmed.
How can this be possible?

In the below-given picture of a pretty girl, there is something wrong. Can you find out what it is?

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

Jim and Sarah are in a long-distance relationship. Jim buys an engagement ring for Sarah and wants to mail it to her. Unfortunately, the only way to ensure the ring will be received is to place a lock on the package. Jim has locks and Sarah has locks, but neither has keys for each other’s locks. How can they make sure the ring isn’t stolen?

In a university, a professor gave a set of three problems to the three brilliant students of his class. See the image for the questions.

John is a strange liar.

He lies on six days of the week, but on the seventh day, he always tells the truth.

He made the following statements on three successive days:

Day 1: "I lie on Monday and Tuesday."
Day 2: "Today, it"s Thursday, Saturday, or Sunday."
Day 3: "I lie on Wednesday and Friday."

On which day does John tell the truth?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

Take away the whole and some still remain. What is it?