The scale is used to measure the magnitudes of earthquakes and predict their effects.

Options

A. Richter
B. Seismograph
C. Electroscope
D. None of them

Answer

To answer the question about the scale used to measure the magnitudes of earthquakes and predict their effects, we can break down the information as follows:

### Step-by-Step Solution:

1. **Understanding Earthquake Measurement**:
- Earthquakes are measured using specific scales that quantify their magnitude and intensity.

2. **Identifying the Correct Scale**:
- The most commonly used scale for measuring the magnitude of earthquakes is the **Richter scale**. This scale assigns a single number to quantify the amount of seismic energy released by an earthquake.

3. **Seismographs and Seismograms**:
- A **seismograph** is an instrument that detects and records the vibrations caused by seismic waves during an earthquake.
- The output of a seismograph is called a **seismogram**, which visually represents the seismic activity.

4. **Understanding the Effects of Earthquakes**:
- The effects of earthquakes can be predicted based on the magnitude measured on the Richter scale. Higher magnitudes indicate stronger earthquakes that can cause more damage.

5. **Conclusion**:
- Therefore, the scale used to measure the magnitude of earthquakes is the **Richter scale**, and it helps in predicting the potential effects of the earthquake.

### Final Answer:
The Richter scale is used to measure the magnitude of earthquakes and predict their effects.

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