What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

Can you fill the blank with the correct number?

6 30 870 756030 _____

If eleven plus two equals one, what does nine plus five equal?

Which is the rope you never skip with?

Complete the series by replacing "?" with the correct number.

ST ND RD TH '?'

John, Jack and Jill are in a desert. John doesn't like Jill and hence decides to murder him. He poisons the water supply of Jill. Since it is a desert area, Jill must drink or he will die of thirst.

Jack does not know of the actions of John and also decides to murder Jill. To succeed in his ill motives, he removes the water supply of Jill so he dies of thirst.

Jill dies due to thirst. Who murdered Jill?

How can you drop a raw egg from a height onto a concrete floor without cracking it?

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

A detective visits his friend John just to discover that John's neighbour Dr Jacob was murdered. Dr Jacob, who is a mathematician wrote the murderer's name in a code word "Hcqtfz". There were five suspects
1. Ajit
2. Pankaj
3. Ganpat
4. Deenu
5. Hariya

The Detective was instantly able to find the murderer.
Can you?

I know a nine-letter word having only one vowel.
Do you ?