Find the Next Number in the Sequence

2 9 3 1 8 4 3 6 5 7 ?

What is the difference between a jeweller and a jailer?

What does this mean?

CCCCCCC

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?

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

You need to complete the maze by entering from the entrance marked below in the figure near the yellow circle, bottom left and leaving from the exit point near the green circle, bottom middle.

Rule of Game: You can move only by exchanging green and yellow circles.

Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

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

A woman named Maria was at the funeral of her mother. She met a nice young man that she had never seen before and after the service, they spent a bit of time together. Then she got busy and didn’t get his name or phone number before he left. She tried to find him, but no one knew who he was or how to contact him. A few weeks later, Maria’s older sister dies and the police suspect murder. Who killed the sister?

If you say my name, I will no longer exist. What am I?