Answer:
Humans have breached this cycle by digging up fossil fuels and burning them, leading to carbon dioxide building up in the atmosphere faster than natural systems can soak it up. This has led to a net increase in greenhouse gases in the atmosphere, causing the planet to heat up.
Explanation:
I believe its D. It becomes more difficult for the cell to get enough oxygen and nutrients.
Increased in pitch (frequency). It's the doppler effect.
Wait a min. Let me look it up
The answer would be ZOO!
