Normal, clean rain has a pH value of between 5.0 and 5.5, which is slightly acidic. However, when rain combines with sulfur dioxide or nitrogen oxides—produced from power plants and automobiles—the rain becomes much more acidic. Typical acid rain has a pH value of 4.0.
Natural selection provides the outline of an explanatory theory." Biologists consider it to be a scientific fact that evolution has occurred in that modern organisms differ from past forms, and evolution is still occurring with discernible differences between organisms and their descendants.
Answer: volcanoes
Explanation: geothermal electricity- generating plants are most commonly located around the Ring of Fire, which is a hotspot for volcanoes.
