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In March 2011, the Fukushima Daiichi nuclear power plant in Japan experienced a meltdown; consequently, radioactive materials were released into the environment. On the International Nuclear Event Scale (INES) running from 0 (indicating an abnormal situation with no safety consequences) to 7 (indicating an accident causing widespread contamination with serious health and environmental effects), the incident received a rating of 7. The only other recorded level 7 incident is the Chernobyl (Ukraine) meltdown in 1986.
One of the radioactive materials released during the Fukushima disaster was cesium-137; cesium-137 has a half-life of 30.2 years. How long will it take for this material to lose the following amount of its radioactivity?
a. 90%
b. 99%
c. 99.9%
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Mathematics: A Practical Odyssey
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