Note
eine Menge - a lot of
eine Menge Menschen - a lot of people
die Menschenmenge - the crowd (of people)
you could use 'die Menge' alone for 'the crowd' but only if you had already established the picture of many people being crowded in one place in the mind of your audience.
die Wassermenge - the quantity/amount of water
die Mengenangabe - (the notation of) the quantity
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