Which of the following is not correct?

1. Circum-Pacific Mountain Belt : 70% of world earthquakes
2. Mid Atlantic Ridge: 10% of world earthquakes
3. Mid World Mountain Belt: 20% of world earthquakes
4. Pacific Ring of Fire: 15% of world earthquakes

What is an earthquake? Give one recent example of an earthquake.

Name two man-made causes of an earthquake. Give one example.

What are known as seismic focus and epicentre with respect to an earthquake?