Density is a measure of the amount of weight in an object the mass per volume of an object the size of an object the hardness of an object

Density is measured by "the mass per volume of an object" or option B. Mass is measured by the amount of weight in a object. (option A) The amount of weight is measured by the size of the object, (option C) and the size of the object is often measured by the hardness of an object. (option D)

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