Consider the following statements regarding the earthquakes : I. The intensity of earthquake is measured on Mercalli scale. II. The magnitude of an earthquake is a measure of energy released. III. Earthquake magnitudes are based on direct measurements of the amplitude of seismic waves. IV. In the Richter scale, each whole number demonstrates a hundredfold increase in the amount of energy released. Which of these statements are correct

Consider the following statements regarding the earthquakes : I. The intensity of earthquake is measured on Mercalli scale. II. The magnitude of an earthquake is a measure of energy released. III. Earthquake magnitudes are based on direct measurements of the amplitude of seismic waves. IV. In the Richter scale, each whole number demonstrates a hundredfold increase in the amount of energy released. Which of these statements are correct ?