I travel all around the world but always stay in the corner. What am I?

A mile-long train is moving at sixty miles an hour when it reaches a mile-long tunnel. How long does it take the entire train to pass through the tunnel?

The Federal bank of London is abducted by the robbers. The head of the robbers asked the cashier to empty their money vault to them and when suddenly cashier got a call from her father. To avoid any suspicion, the robber asked the cashier to pick the call and reply her father in the shortest manner possible.

The cashier told her father "Is there an emergency father, Call me when you are free and I will help you in your furnishing" and then the cashier hung up the phone.

After 10 minutes, police arrived at the crime scene.

How did the police know about the robbery?

If an earthquake is 1 point higher on the Richter Scale than another earthquake which is actually 10 times stronger, how much stronger would an earthquake be if it was just half a point higher on the Richter scale?

Find three numbers such that

* When we multiply three numbers, we will get the prime numbers.
* The difference between the second and the first number is equal to the third and second.

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

Bopanna was working on a murder case when he received a message about the location of the murder weapon.
The message was encrypted as below.

"deb mitciv eht edisni neddih si nopaew redrum ehT"

Tell me the location of the murder weapon.

Three ants are sitting at the three corners of an equilateral triangle. Each ant starts randomly picks a direction and starts to move along the edge of the triangle. What is the probability that none of the ants collide?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

If,

A + B = C
D - C = A
E - B = C

Based on the above equations, find out the answer for:

D + F = ?