I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

What has to be broken before you can use it?

Three ants are going up a hill, one behind the other. The last ant then says to the other ants, 'There is an ant behind me!'' How come?

If an electric train is travelling south, then which way is the smoke going?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

What has many keys but can’t open a single lock?

How many times can you subtract the number 5 from 25?

I have a head like a cat and feet like a cat, but I am not a cat. What am I?

How many letters are in the alphabet?

The Puzzle: A girl, a boy, and a dog start walking down a road.

They start at the same time, from the same point, in the same direction.

The boy walks at 5 km/h, the girl at 6 km/h.

The dog runs from boy to girl and back again with a constant speed of 10 km/h. The dog does not slow down on the turn.
How far does the dog travel in 1 hour?