What always comes into a house through the keyhole?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

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

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

Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

Find out a multi-digit number that if multiplied by the number 9 or any of its multiplications products (i.e. 18, 27, 36, 45,..) will result in the multiplication factor repeated (n) number of times.

The centre of the third figure is empty. What digit should fit inside?

I always drive my customer away.

Who am I?

A maths symbol is hidden in the below Bar Graph. Can you decipher it?

Replace the letters of words with a number so that the below equation holds true

BASE +
BALL
---------
GAMES
----------