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A recent investigation by scientists of the US Geological Survey shows that strange animal behavior might help to predict future carthquakes. Investigators found such occurrrences in a ten-kilometer radius of the epicenter of a fairly recent quake. Some birds screeched and flew about wildly: dogs yelped and ran around uncontrollably. Scientists believe that animals can perceive these environmental changes as early as several days before the mishap.
In 1976 after observing animal behavior, the Chinese were able to predict a devastating quake. Although hundreds of thousands of people were killed, the government was able to evacuate millions of other people and thus keep the death toll at a lower level.
Select the appropriate preposition for the blank in the following sentence, "The keys fell ___ the pool of water".
