How is a fly different from a mosquito?

There is one four-digit whole number n, such that the last four digits of n2 are the original number n

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?

Detective Rockford was jogging near the beach at 4:30 am.
He hears a sound near the shack "No Michael, Please Do not shoot me".
Next instance he heard the sound of gunfire. Rockford rushes to the shack where he finds women lying dead and a gun in close proximity of three "Doctore Lawyer and a Teacher".

Rockford immediately knew that the Lawyer has committed the crime. How?

If I put in one bird per cage, I have one bird too many. If I put in two bird per cage, I have one cage too many. How many cages and birds do I have?

What is so fragile that saying its name breaks it?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

A man was just doing his job when his suit was torn. Why did he die three minutes later?

If you read clockwise, you can form a word by inserting three missing letters in the picture given below. Can you do it?

Can you tell a 3D object that has just two surfaces?