<span>The mountains were once seas. The land was forced up by tectonic motion when the mountains were formed. The Sahara also used to be a sea and has a valley full of the fossilized remains of an extinct species of whale. It is generally agreed upon that two plates colliding caused the uplift that created the mountainous zone. Same for the Himalayas.</span>
Anything that is considered alive must exhibit ALL 7 characteristics of life. A virus may show some characteristics, but it does not show all, so therefore, its not alive.
Answer:
The correct answer is statement A.
Explanation:
The procedure of purifying ocean water, that is, the saline water so that it can become suitable for drinking is termed as desalination. Almost 70 percent of the Earth is covered with water and of this only 3 percent is used for drinking purposes. On a huge scale, the process of desalination would require the boiling of water, which would eventually require an enormous amount of energy.
Reverse osmosis and electro-dialysis are the methods used for desalination. However, these procedures are very costly and cannot be performed on a huge level as it can affect the economy of various countries.
