Nuclear fission formula by the looks of it. Possibly how Professor Lisa Meitner realised that she had split the atomic nucleus. The Xenon and the Strontium (Xe and Sr) would presumably show up in a radio chemical assaying test at her university.
A few years later, Professor J Robert Oppenheimer watched a nuclear test somewhere near Los Alamos, US and lamented "I am become death, the destroyer of worlds". Shortly thereafter, Hiroshima and Nagasaki were razed to the ground and annihilated by nuclear bombs. Professor Meitner, probably inadvertently, had got the keys to the doors to "nuclear hell", and JRO ended up turning them. Something like that maybe, and a very harrowing and tumultuous period in human history.
Note in the fission equation, that out come two neutrons. They go off and produce a similar fission in another U235 nucleus into a chain reaction which, i not moderated by, say, Boron, can end up as a "mushroom cloud".
Answer:
1. A satellite is an object which has been sent into space in order to collect information or to be part of a communications system. Satellites move continually round the Earth or around another planet.
2. red giant
3.red giant.
Explanation:
Hey there! :D
We want to find an answer choice that is reversible. If the physical change could have some way of being fixed, then it is a physical change. If it is a chemical change, the make-up is different and there is no way that it could change.
A cookie baking cannot be reversed. Cookies cannot go back to being cookie dough.
Paper burning cannot be reversed. Ashes and smoke cannot go back to being paper.
However, if your ice cream melts, you can refreeze it. Therefore, "3" is the best answer to the question.
I hope this helps!
~kaikers