The ice caps in the North pole of Mars compose of frozen water and frozen carbon dioxide and the ice caps on the South Pole consists mainly of of frozen water.
Frozen. In glaciers and icecaps.
2%
Frozen in the icecaps (in the form of ice at the poles).
The current - 2014 - estimation is about 70%.
Some difficulties that could arise include the high cost and energy required to transport the frozen water from the polar icecaps to the US, the environmental impact of extracting water from these sensitive ecosystems, and potential geopolitical tensions over control and access to this valuable resource. Additionally, the logistics of storing and distributing frozen water on such a large scale would pose significant challenges.
The brain is mostly composed of water, fat, and proteins.
Charon is covered in water ice and rock, but it does not have soil or gravel like Earth. Its surface is mostly composed of frozen water and some rocky material.
water
There is approximately 1,386,000,000 km3 of water on Earth, which includes all the water within the oceans rivers, lakes, groundwater, atmospheric water, and frozen water (i.e. snowcover and the icecaps).
The poles on Mars are primarily white in color. This is because they are composed mostly of frozen carbon dioxide (dry ice) and water ice. The combination of these frozen substances gives the poles their distinctive white appearance.
According to NOAA: "Of the three percent of the water that is not in the ocean, about 69 percent is locked up in glaciers and icecaps. Ninety percent of that frozen water is in Antarctica and about nine percent covers Greenland."
Ocean