Eight of us go fourth, not back, to protect our king from an attack. What are we?

I went to the bookshop and spent one-half of the money that was in my purse.

When I came out, I found that I had as many cents as I had dollars and half as many dollars as I had cents when I went in. Find the money in my purse when I entered the store.

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

A woman lives in a skyscraper thirty-six floors high and is served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

Can you discover the missing number in this series?

37, 10, 82
29, 11, 47
96, 15, 87
42, ?, 15

As shown in the image, the nine Dogs are square fenced. By constructing just two square fences can you make sure that two Dogs cannot meet each other without crossing the fence?

I am Huge on Sunday and Saturday.
I am small from Tuesday to Thursday.
I do not exist on Monday and Friday.
Who am I?

1. Where does Easter come from before Valentine's Day?

2. Do you know what is in the middle of Valentine's?

3. What did the lady bee say to the man bee on the occasion of Valentine's Day