What kind of band never plays music?

You can see it everyday, But cannot touch it at will. What is it?

A thief enters a store and threatens the clerk, forcing her to open the safe. The clerk says, “The code for the safe is different every day, and if you hurt me you’ll never get the code.” But the thief manages to guess the code on his own. How did he do it?

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?

John speaks the truth only once a day in a week. Below are a few hints for you:

First: Days are Sunday, Monday and so on.
Second: One day he says, "I lie on Monday and Tuesday".
Third: On the next day, he says, "Today is either Thursday, Saturday or Sunday".
Fourth: On the next day, he says, "I lie on Wednesday and Friday".

Can you identify the day on which he speaks the truth?

When can we add 2 to 11 and get 1 as the correct answer?

There is a place where if I stand up straight, I will still be considered sideways.

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

John is found dead in a bare field. Nobody killed John,
John did not commit suicide.

Inspector Jacob found a bag just a few meters away from John which could save his life. What was in the bag?