Answer:
Food famish, civil wars, climate changes, ect.
Explanation:
It is already simplified unless the variables have a value
Mars (diameter 6790 kilometers) is only slightly more than half the size of Earth (diameter 12750 kilometers).
Answer:
The sun
Explanation:
The sun drives the water cycle. The sun evaporates water from the oceans, seas, lakes and other bodies of water and also from plants through the process of transpiration. The evaporated water then forms into clouds and when it gains enough mass it falls back to Earth. This is a closed system so that means that this is the same amount of water that has always been present on Earth.