| Water is the oldest form of transport.
The original sailing vessels were replaced by steamboats in the early
1800s and by diesel power in the 1920s. A distinction is generally made between
deepwater and navigable inland water transport. Domestic commerce centers on
tile Great Lakes, canals, and navigable rivers. In 1975 water transport accounted for 22.6 percent of total intercity tonnage. Its relative share of intercity tonnage was 31.3 percent in 1947 and 31.7 percent in 1958. Tonnage declined to 27.9 percent in 1965 but increased by 1970 to 28.4 percent. This short-term increase did not stabilize. Market share dropped by 5.8 percent by 1975. Forecasted market share by 1985 is 18.4 percent of total intercity tonnage. The water transport share of revenue has been less than 2 percent of intercity freight revenue since 1955. The exact miles of impro A. Steamboats are the original sailing vessels. B. Steam power followed diesel power. C. Deepwater and navigable inland water transport are equivalents. D. There is domestic commerce in the Atlantic Ocean. [简答题]If you’ve seen water form on the side of a cold drink, you’ve seen______.
[填空题]The preliminary form of flood emerges when water______ in a certain piece of land.
[填空题]
Where did the classical music originate [填空题]According to the schedule, the Project was originally planned to finish in February next year.
[简答题] Water Problems
Where’’s the water
Water. If you’’ve got it, you probably take it for granted. But a quick look at the globe — and a chat with the tiny group of researchers who are worrying about fresh water — both indicate that water shortages are very serious.
And they aren’’t necessarily in the future, either. Here’’s what we’’ve read in the past week or so.
... Mexico City (home to 20 million people) is sinking because the city sucks out underground water faster than the aquifer can be refilled.
... Florida wants to refill its overpumped aquifer (蓄水层) with untreated surface water, despite federal regulations to the contrary.
... Texas is moving toward private, for-profit water sales. The water will be "mined" from aquifers that are disappearing fast. No word on what the private suppliers, including corporate raider T. Boone Pickens, will do once the aquifers run dry.
... Aquifers around the world are being overtapped for i
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