You need to pick one entry from pot A and one from pot B to have a perfect match. Can you do it?

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

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

A little girl goes to the store and buys one dozen eggs. As she is going home, all but three break. How many eggs are left unbroken?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

He digs out tiny caves and stores gold and silver in them. He also built bridges of silver and made crowns of gold. They are the smallest you could imagine. Sooner or later everybody needs his help, yet many people are afraid to let him help them. Who is he?

A man is found unconscious in front of a store at two in the morning. His head is bleeding and there’s a brick laying next to him. When the police arrive, they carry the man to jail. Why did they arrest him?

What Does this text mean:

important=important

A man and a dog were going down the street. The man rode, yet walked. What was the dog’s name?

There are three light switches outside a room. One of the switches is connected to a light bulb inside the room.
Each of the three switches can be either 'ON' or 'OFF'.

You are allowed to set each switch the way you want it and then enter the room(note: you can enter the room only once)

Your task is to then determine which switch controls the bulb?