Consider the following statements regarding the earthquakes: 1. The intensity of earthquake is measured on Mercalli scale. 2. The magnitude of an earthquake is a measure of energy released. 3. Earthquake magnitudes are based on direct measurements of the amplitude of seismic waves. 4. In the Richter scale, each whole number demonstrates a hundredfold increase in the amount of energy released. Which of these statements are correct?

1. Statement 1 is correct: Earthquake intensity refers to the severity of shaking and its effects at a particular location. It is measured using descriptive scales like the Modified Mercalli Scale (MMI). 2. Statement 2 is correct: Earthquake magnitude is a quantitative measure related to the total energy released at the earthquake's source (hypocenter). 3. Statement 3 is correct: Earthquake magnitudes, particularly on scales like the Richter scale (ML) or surface-wave magnitude (Ms), are calculated based on the measurement of the maximum amplitude of specific seismic waves recorded by seismographs, adjusted for distance. 4. Statement 4 is incorrect: The Richter scale is logarithmic (base 10) with respect to wave amplitude. Each whole number increase represents a tenfold increase in measured amplitude, but it corresponds to approximately a 32-fold increase in energy released, not a hundredfold increase. 5. Therefore, statements I, II, and III are correct.