GMAT Sentence Correction (SC) | Re: The Greek mathematician Archimedes is most famous for discovering that

"Quantities of water" is wrong. This seems to be an oversight by the author.

First: water is neither singular nor plural. It is uncountable.
Second: In constructions such asquantity of X, amount of X, number of X,[ etc/i] the words [i]quantity, amount, number etc. are never plural (irrespective
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