I make two people out of one. What am I?

A crime was committed at baker street. Ibrahim Dakota who was shot in the stomach was the main suspect. Sherlock questioned the suspect. The conversation started as:
Sherlock: What's your story, Ibrahim?
Ibrahim: I was walking around baker street and suddenly a man from the back shot me. I ran as fast as I could to save my life".
Sherlock: That is enough (and ask the police to arrest him).

Why does Sherlock think he is the murderer?

A plane crashed between the border of Mexico and America. Where do you bury the survivors?

Outside a tattoo artist's shop, there was a signboard which read 'I make tattoos on only them who do not tattoo themselves'.

Reading it what do you think, does the tattoo artist tattoo himself?

John is asked to stand behind Jacob and Jacob is asked to stand behind John. Both of them feel confused about it and don't know what to do?

But it is quite possible, do you know how?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

A man died, leaving $10,000,000 for his widow, 5 sons and 4 daughters. Each daughter received an equal amount, each son received twice as much as a daughter, and the widow received three times as much as a son.

How much did the widow receive?

All of you like to eat me. I am a five-lettered word. Remove the first two and I turn into an infamous animal. Remove just the first and I become a heinous crime. Remove the first and the last and you can groove on me.

Can you guess who am I?

You bought me for dinner but never eat me. What am I?

What has lots of eyes, but can’t see?