Force... I hope this helped you
Answer:
Explanation:
Energy can neither be created nor destroyed, but it does change its form. And not all forms of energy are usable and it gets dissipated as heat energy and sound energy. ... Moreover, the current sources or energy such as fuels are non-renewable in nature and are rapidly consumed. That is why we are facing energy crisis.
The answer is Strontium(Sr). The reactive increase from right to left. And this element has two valence electrons. So Rb is not correct. Then the very reactive metal is Sr.
<em>In the late 1800's, experiments using cathode ray tubes led to the discovery of the;</em>
Electron(s)
<u>It was founded that many different metals release cathode rays, and that cathode rays were made of electrons, very small negatively charged particles.</u>