Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10

Can you fill the blank with the correct number?

6 30 870 756030 _____

What has many teeth, but cannot bite?

A boy was driving a car, a girl took a lift from her. She asked his name. The boy said - my name is hidden in my car’s number, find it if you can. After this, she got down Car number was [ WV733N ] Can you guess the name now?

Replace the question mark with the correct number.

A boy was at a carnival and went to a booth where a man said to the boy, "If I write your exact weight on this piece of paper then you have to give me $50, but if I cannot, I will pay you $50." The boy looked around and saw no scale so he agrees, thinking no matter what the carny writes he'll just say he weighs more or less. In the end the boy ended up paying the man $50. How did the man win the bet?

our enemy challenges you to play Russian Roulette with a 6-cylinder pistol (meaning it has room for 6 bullets). He puts 2 bullets into the gun in consecutive slots, and leaves the next four slots blank. He spins the barrel and hands you the gun. You point the gun at yourself and pull the trigger. It doesn't go off. Your enemy tells you that you need to pull the trigger one more time, and that you can choose to either spin the barrel at random, or not, before pulling the trigger again. Spinning the barrel will position the barrel in a random position.

Assuming you'd like to live, should you spin the barrel or not before pulling the trigger again?

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??