Question:
Use evidence from the fact that as the population of plants decreases , carbon in the atmosphere will increase to answer the following question. "Which would increase atmospheric carbon by the lowest degree?"

Answer:
trees

Question:
Use evidence from the fact that precipitation is when rain fall from clouds to the Earth to answer the following question. "Precipitation sometimes leads to"

Answer:
caves

Question:
Use evidence from the fact that Matter in the gas phase has variable volume to answer the following question. "Which is least likely to have a constant volume?"

Answer:
car exhaust