The Land of Israel: Terumah, Ma'aser, Shmittah and Yovel, Kilayim: An Omer:
How much is an Omer?
An omer is the volume of 43.2 eggs; but there is a dispute about the volume
of an egg for halachic purposes. Some say that an omer is 2510 cubic
centimeters (which is about the volume of 43 of today's eggs), but others
say that it's 4320 cc (so that the volume of an egg is 100 cc).
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