Often, the rock layers bookending the mass extinction are noticeably different in their compositions. These changes in the rocks show the effects of environmental disturbances that triggered the mass extinction and sometimes hint at the catastrophic cause of the extinction
Chemical reactions can be identified when there is a change in color, energy is produced, change in odor, or if new substance forms.
Answer:
Your answer is Gravity,
The Earth's gravity pulls things at a rate of 9.8m/s² (varying depending upon one's distance). according to Newton, "all mass in the universe exerts some gravitational force". you are pulling on Sagitarios A* (the black hole at the center of the milky way galaxy) right now, and it is also pulling on you.
If you have any questions I <em><u>insist</u></em> that you ask in the comments.
<em>Wbob1314</em>
wrong. If its for the study island its potential energy only.