It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

I am a type of room you cannot enter or leave. Raised from the ground below, I could be poisonous or a delicious treat. What am I?

A father's child, a mother's child, yet no one's son.

Who am I?

If an earthquake is 1 point higher on the Richter Scale than another earthquake which is actually 10 times stronger, how much stronger would an earthquake be if it was just half a point higher on the Richter scale?

Replace the question mark in the picture below.

How can one talk without saying a single word?

When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

Solve below popular number sequence
314 159 265 358 979 323 846 ?

Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?

Can you find a rabbit in the given picture?