Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

[EX Q]: Question: What is formed when nitrogen and sulfur oxides dissolve in rain? Answer: acid rain
[EX A]: Acid rain is rain that has a pH less than 5. It forms when nitrogen and sulfur oxides dissolve in rain. Acid rain kills living things and damages buildings and statues.

[EX Q]: Question: Groundwater does what to the rock beneath the ground surface? Answer: erodes it
[EX A]: Groundwater erodes rock beneath the ground surface. Limestone is a carbonate and is most easily eroded.

[EX Q]: Question: What transmits nerve impulses to other cells? Answer: neurons
[EX A]:
Neurons transmit nerve impulses to other cells.