The answer you are looking for is "<span>a. elements of ecosystems are mutually dependent on each other ".</span>
Information from deep-ocean exploration can help predict earthquakes and tsunamis and help us understand how we are affecting and being affected by changes in Earth's environment. Ocean exploration can improve ocean literacy and inspire young people to seek careers in science, technology, engineering, and mathematics.
A wall stands using gravity. It is constantly being pulled down. Many also place them in ways that they dig into the ground, and almost make a socket just for the wall to be placed, using the land that is there. More and more walls are placed and eventually, they make flooring and a roof.
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