Which statement about the Mercalli scale is true?

Question

The scale has twenty ratings for an earthquake’s effects.
The scale rates an earthquake based on its total energy released.
The scale rates an earthquake according to how much damage it causes.
The scale is most useful when scientists use data from three or more seismographs.

Answer 1

The true statement about the Mercalli scale is:

The scale rates an earthquake according to how much damage it causes.

The Mercalli Intensity Scale measures the effects and damage of an earthquake based on observations and reports, rather than measuring the earthquake's energy release like the Richter or Moment Magnitude scales.