It would be “To obey the law of conservation of mass”
Answer:

Explanation:
Hello,
In this case, we need to remember that for the required time for a radioactive nuclide as radium-226 to decrease to one half its initial amount we are talking about its half-life. Furthermore, the amount of remaining radioactive material as a function of the half-lives is computed as follows:

Therefore, for an initial amount of 100 mg with a half-life of 1590 years, after 1000 years, we have:

Best regards.
Answer:
no, and next time take it right
Explanation:
8. The picture that would best represent atoms in the gas of a neon sign is the image B. This
is because they have room for movement in that their distance between each
particle is great. That is why gases has greater volume compared to liquids and
solids.
<span>9. The picture that would best represent a rock is the image C. The solid molecules are so pact that they have no room for movement.</span>