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

During which month do people sleep the least?

What you cannot hold but it is yours?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

Twenty frogs are sitting on a log floating on the surface of a river. Two of them decide to jump off into the water.

How many frogs are there on the log at this moment?

This is a most unusual paragraph. How quickly can you find out what is so unusual about it? It looks so ordinary, you'd think nothing was wrong with it. Actually, nothing IS wrong with it. But it is not as ordinary as you might think. If you think about it for a bit, you will find out why it is truly so unusual. So what is it? What is so unordinary about this paragraph?

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

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

Which Burger Is Different in below image?