Answer:
Check explanation
Explanation:
Gold - Au (Aurum)
Mercury - Hg (Hydrargyrum)
Copper - Cu (Cuprum)
Iron - Fe (Ferrum)
Lead - Pb (Plumbum)
These elements in the periodic table are some of the elements represented by letters not in line with their names.
This is because, these elements were known in ancient times and therefore, they are represented by letters from their ancient names.
The answer is D. As the ambulance gets closer, the sound waves are compressed relative to the person; so the frequency increases.
The correct answer is A. Acid rain forms from human activities and lowers the pH of rainwater below 7
Explanation:
The term "acid rain" is used to refer to rainwater with a low pH or a high acidity, this includes rainwater with a pH below 7 (solutions with a pH under 7 are acidic). In terms of formation, acid rain is mainly the result of human activities such as factories or cars that release pollutants into the atmosphere including nitric and sulfuric acids and these alter the natural pH of rain and makes it more acidic. Additionally, acid rain has negative consequences such as the death of fishes and other organisms in lakes, rivers, etc. because the acidity is toxic to many organisms. Thus, acid rain is the result of human activities and it lowers the pH of rain (Option A).
