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99. Richter Scale The common logarithm is used to measure the
intensity of an earthquake on the Richter scale. The Richter
scale rating of an earthquake of intensity I is given by
log(1) log(lo), where Io is the intensity of a small "bench-
mark" earthquake. Write the Richter scale rating as a single
logarithm. What is the Richter scale rating of an earthquake
for which 1= 1000-I?
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