Man is a land animal, but he is also closely tied to the sea.【B1】______histo

Man is a land animal, but he is also closely tied to the sea.(26)Throughout history the sea has survived the needs of man. The sea has provided man with food and(27)a convenient way to travel to many parts of the world. Today, experts(28)estimate that nearly two-thirds of the world’s population lives within eighty kilometers of the seacoast.
    In the modern technological world the sea offers many resources to help mankind(29)survive. Resources on land are beginning to grow less. The sea, however, still offers hope to(30)supply many of man’s needs.
    The riches of the sea yet to be developed by man’s technology are(31)impressive. Oil and gas exploration has existed for nearly thirty years. Valuable(32)amounts of minerals such as iron, nickel and copper exist on the ocean floor, ready to be(33)mined.
    Fish farming promises to be a good way to produce large quantities of food. The culture of fish and selfish is an ancient skill practiced in the past mainly by(34)oriental peoples.
    Besides oil and gas, the sea may offer new sources of energy. Experts believe that the warm temperature of the ocean can be used in a way similar to that of the steam in a steamship. Ocean currents and waves offer possible use as a source of hydroelectric power.
    Technology is enabling man to explore even deeper under the sea. New undersea technology is providing divers with diving suits and(35)undersea chambers that are kept at sea-level pressure. The development of strong, new materials has made this possible.