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The present study examined the dependence of difference tone level [ L ( f2 - f1 ) ] on the following parameters of the two - tone input : f1 , f2 / f1 ( f2 greater than f1 ) , L1 , L2 , and L1 = L2 .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
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