Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

You are given a cube that is made with the help of 10x10x10 smaller cubes summing up to a total of 1000 smaller cubes. You are asked to take off one layer of the cubes.
How many remain now?

Spelt forwards I’m what you do every day, spelled backwards I’m something you hate. What am I?

A worker is to perform work for you for seven straight days. In return for his work, you will pay him 1/7th of a bar of gold per day. The worker requires a daily payment of 1/7th of the bar of gold. What and where are the fewest number of cuts to the bar of gold that will allow you to pay him 1/7th each day?

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?

The first two letters signify a male, the first three letters signify a female, the first four letters signify a great, while the entire world signifies a great woman. What is the word?

I always drive my customer away.

Who 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?

Make eight squares by moving only two matchsticks.
Note- Square can be of different sizes.

Which is faster, Heat or Cold ? Explain.