I think it's the first one and the third one. Not completely sure though.
Gravity??? Honestly don’t know.
Warm, dry air. Hope this helps
Answer: It’s how the post office know which zone to drive to and how to sort it better
Explanation:
Answer:
It happens because the consuming is higher than the water drop rate, or even because there are too many people in a zone where there is not enough fresh water.
