Isotopes of carbon or any element
Radiation, Chemical agents and viruses may all cause C. Generic Mutations.
Answer:
I think the answers D. Hope this helps you.
Explanation:
He could be blindfolded and know which was his and which was his sister's. All he would need to do is pick them both up and if they were too big then pick them up one at a time. The lumber might make it harder to tell, but this is a question about physical properties.
So there is a change in mass which for the purpose of this question should be quite different. His sister's ought to be much lighter than his. He would find it easier to pick up.
