Question: Sentence 1: A drop of each sample was analyzed.
Sentence 2: There is not a drop of pity in that man.
Does drop mean the same thing in these two sentences?
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Answer: the same meaning

Question: Sentence 1: There was a chemical reaction of the lime with the ground water.
Sentence 2: His reaction to the news was to start planning what to do.
Does reaction mean the same thing in these two sentences?
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Answer: different meanings

Question: Sentence 1: He was arrested on a charge of larceny.
Sentence 2: The charges against the estate.
Does charge mean the same thing in these two sentences?
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Answer:
different meanings