Which is the best way to determine if an object is made of pure silver

The Nitric Acid Test

Explanation:

The Nitric Acid Test is used to check if silver is pure or plated. To do so, file a small part of the item in a discreet area where it cannot be seen. Apply a few drops of nitric acid. If the area turns into creamy white, the silver is pure or sterling. If green, it is probably fake or silver-plated.

your answer would be a. 12.5 kg

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