It is true 90 percent of water covers the earth.
The Crust - The crust is Earth's solid and rocky outer layer, including both the land surface and the ocean floor.
The total amount of water as a percentage of all the mass that makes up our planet is estimated at 0.023%. A little over 2/3 of the Earth is covered by water; to be more precise, the consensus is 70.8% (71%) of the surface is water, 29.2 % is land.
The ocean is made of water thus all layers contain the same amount of water.
The ocean is considered an ecosystem. 70 percent of the earth is made up of ocean water.A+-- Marine
The crust contains the ocean floor and also the continents on Earth.
The Earth is covered with 71 percent by oceans. The oceans hold close to 97 percent of all Earth's water.
The Indian Ocean
In the ocean
The Arctic Ocean covers roughly 9% of the Earth's surface.
97% of the earth contains salt ocean water because of the seven seas on earth.