Modes of Transportation There are a variety of means for trans

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问题                Modes of Transportation
   There are a variety of means for transportation. Usually,
   the choice of transportation depends on the【1】______ of goods【1】______
   and the points of distribution.
   There are five major means of transportation: railroads,
airplanes, ships, trucks, and pipelines. Often, goods may be
transported by a combination of【2】______                        【2】______
     Railroads are best adapted to the transportation of
【3】______ products that are low in value in relation to their   【3】______
weight. Truck lines are effective for transporting high-value
goods short distances. With the【4】______, trucks can reach      【4】______
almost every destination without【5】______ goods. Air freight    【5】______
used to be a means to speed【6】______ or expensive but light     【6】______
products, but this changed with the introduction of【7】______    【7】______
Transportation by waterways is characterized by low cost and
low speed. A new development is the use of【8】______ ships.      【8】______
    Pipelines are a special form of transportation mainly used
to move gasoline, crude oil and【9】______ , but they can also    【9】______
move【10】______ like coal.                                       【10】______ [br] 【10】
Modes of Transportation
   There are many means of transportation, and each has its advantages and disadvantages. Sometimes, however, the nature of the goods and the points of distribution limit a firm’s transportation choices.  Messages can be transported by wire, airwaves, and beams of light; McDonald’s hamburgers cannot.
   Railroads, airplanes, ships, trucks, and pipelines are our major means of transportation. Goods are often transported by a combination of carriers. Truck trailers, for example, are loaded on flatcars and transported by rail to their destination, where a tractor hitches up to the trailer and speeds the goods on to another point.  Ships and barges also are equipped to carry trailers.
   The important factors to be considered by a manager who must select modes of transportation are cost and time, for shipping time is an important cost.  g recent study of how best to ship fancy fruits from the Pacific Northwest to Scandinavia showed that it would be profitable to fly them by jet-cargo aircraft.  The question then arose about what cargo should be flown back.  After extensive study, it was decided that the return cargo should be automobiles.
   Railroads are best adapted to the transportation of bulk products that are low in value in relation to their weight and that must travel great distances.  Because trains can go only where there are tracks, railroads can directly serve only points on railroad lines.  Piggyback loading of trailers, however, allows the advantages of rail and truck combinations.
   Truck lines are effective for hauling high-value goods short distances.  The highway system permits trucks to reach almost every point in the nation and make deliveries directly to destinations without transferring goods.  Trucks can stop within a city and move freely from warehouse to retailer and from retailer to consumer.  In combination with railroads, trucks can move goods long distances and make delivery directly without unloading and reloading.
   Over the past two decades, the use of air freight has increased greatly.  Once thought of as a means to speed perishables or expensive but light products, air freight now uses high speed, supercargo planes, developed for military operations, to move bulk goods.  If tanks and cannons can be carried by plane,  so can many industrial and consumer products. Containerization permits more efficient use of space in planes, and the speed of air transport allows great efficiency.
   Helicopters have been used to ship large items that could not conveniently be carried by other means. Whole fabricated houses have been moved by helicopters from factory to home site, set on the foundation, and made livable by nightfall.  The airplane can land only at airports.  The helicopter can land almost anywhere.  In rugged timber country, it has proved cheaper to use helicopters than to build roads for trucks.
   Waterways have long served for transportation.  Cargo ships and barges move bulky goods at low cost—and low speed. The loading of truck trailers directly onto ships and barges brings some flexibility to water transportation.  Barges moved by tugboats have long been used to move railroad cars.  To overcome bad weather, even submarine transport has been tried.
   New developments in water transportation include container ships, Large quantities of goods can be stored in their holds and also in standardized and easy-to-handle containers on the decks. New superships—the oil tankers—are too big for many harbors, so offshore ports are being constructed for unloading.
   Pipelines are a special form of transportation used mainly to move gasoline, crude oil, and natural gas. It is now possible to move different petroleum products through a pipeline at the same time.  Some solids have also been moved by pipeline.  The Cleveland Electric Company uses a great deal of coal.  When railroad freight rates rose, the company built a pipeline from the coal mines in West Virginia to Cleveland.  The coal was ground into a powder that was mixed with water to form a slush.  The slush was hydraulically moved through the pipeline to Cleveland, where it was dried and burned. Many solid products could be moved in this manner.  Pipelines usually move fluids, but in the future air or hydraulic action may help to move many other goods through them.

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答案 solids/solid materials

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