I believe it's answer #3. Logically, at least.
You can test #1 through trial and error.
You can experiment #2 also through trial and error.
You cannot test #3 through trial and error, because that would be catastrophic.
You can test #4 through a survey and individual study and data collection.
There would be 79 electrons present in each atom of gold. I hope this helps :)
Answer:I am not sure how
Explanation: sorry free trial
I think it would be the sun because it’s the one giving energy to most things, and if you haven’t answered it yet you can put the sun because it’s giving energy to the plans and the environment and it’s the the sun was the effect of the whole thing, sorry if I didn’t help