I am an odd number. Take away a letter and I become even. What number am I?

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

Why is a river so rich ?

There was a kingdom in which the king had no heir to take over his thrown. Even the queen was dead and he himself was on the verge of dying. He thought about it and then summoned all of the teenagers. He gave one seed each to all of them and asked them to grow the plant. He announced that the one with the most beautiful plant will become the king/queen of the empire after the death of the king.

After a month, all of them were called. The king looked at all of the plants but announced the girl with an empty pot as the queen of the empire. Why?

Complete the table series riddle by finding the number that can replace "??".

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?

The horse jumps over the king.
Strangely there is absolutely no scratch on him.

Can anyone explain, how is this possible?

I have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99