Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

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?

Speaking of rivers, a man calls his dog from the opposite side of the river. The dog crosses the river without getting wet, and without using a bridge or boat. How?

When is the top of a mountain similar to a savings account?

Solve the following series:
AZ, GT, MN, __, YB

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

What number divided by 4 is the same as that number minus 4?

If all the below statements are true

1. Gianni was either in Italy or France in 1997.
2. If Gianni did not kill Versace, Hilton must have killed him.
3. If Versace died of suffocation, then either Gianni killed him or Versace committed suicide.
4. If Gianni was in Italy in 1997, then Gianni did not kill Versace.
5. Versace died of suffocation, but he did not kill himself.

Who killed Versace and where was Gianni in 1997?

The measurement of time, That can't be found on a clock, But can be looked upon on a map.

Who is He ?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?