Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.   

   The Richter scale is a numerical logarithmic scale developed and introduced by Charles R. Richter in 1935 to measure the amplitude of the largest trace recorded by a standard seismograph one hundred kilometers from the epicenter of an earthquake. Tables have been formulated to demonstrate the magnitude of any earthquake from any seismograph. For example, for a one- unit increase in magnitude, there is an increase of thirty times in released energy. The Richter scale considers earthquakes of 6. 75 as great and 7. 0 to 7. 75 as major. An earthquake that reads 4 to 5. 5 would be expected to cause localized damage, and those of magnitude 2 may be left. It is estimated that almost one million earthquakes occur each year, but most of them are so minor that they pass unnoticed.

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