Help please please brainy please

A

Explanation:

The characteristic physical property of a substance will stay the same regardless of the amount of matter. The density, thermal conductivity, and boiling point of a substance will not change from the amount of matter, so the answer is A, mass. The mass of anything will change with the amount sampled.

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Good luck

i heard they are taking it off i hope this isn't true but otherwise if it doesn't get taken off it will probably be in early december or early january of 2018-2019