Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

Who are the happiest people in IPL match?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Below, you can see three complete equations and one incomplete. Based on the three complete ones, can you complete the incomplete one?

5 $ 4 $ 3 $ 9 = 4215
6 $ 9 $ 2 $ 6 = 3816
4 $ 7 $ 3 $ 3 = 1122
7 $ 2 $ 7 $ 4 = ____

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?

I have a head like a cat and feet like a cat, but I am not a cat. What am I?

Christina is practising her dance steps along with her friends. In a particular sequence, all of them form a row. At that point, Niharika is standing in the 4th position from either end of the row.
Can you find out how many girls are practising together?

In the picture, you can see a chess board. On the top left position, the K marks a knight. Now, can you move the knight in a manner that after 63 moves, the knight has been placed at all the squares exactly once excluding the starting square?

If you read clockwise, you can form a word by inserting three missing letters in the picture given below. Can you do it?

There is a straight highway. Four different villages lie on that highway. The distance between them is different. The third village is 60km away from the first village; the fourth is 40 km away from the second; the third is 10 km near to the fourth that it is to the second.

Can you calculate the distance between the fourth and the first village ?