I believe the answer is: <span>prisoners and guards
The purpose of study is to find out how human would behave when given complete authrority towards other humans.
As it turned out, the participants who were assigned as guards started to use their power to abuse the participants who were assigned as prisoners, and researchers were forced to stop the experiment.</span>
Didn't let me send text so here is a png hope i hellpled
That would be trading and farming.
The correct answer is D) There would likely not be life on Earth because its surface would be much colder and Earth's water would be frozen.
Life on Earth could be affected if the atmosphere did NOT contain greenhouse gases in the following way: "There would likely not be life on Earth because its surface would be much colder and Earth's water would be frozen."
Scientists agree that this is basically the importance of greenhouse gases on the atmosphere of planet earth. Without these gases, the surface of the earth would have an average temperature of minus 18 centigrades. Many life forms as we know them could not survive under this hairs climate condition. Furthermore, most of the surface of the earth would be covered on ice.