A need for beauty, lightness, corrosion resistance, or other specific prope

游客2024-10-30  10

问题      A need for beauty, lightness, corrosion resistance, or other specific properties must be present before plastic can be considered as competitors of brick, window glass, cement, cast iron, or steel, since volumetric prices are so low for the last substance and for wood. It is not particularly unfortunate that plastics do not appear economical for every use. There is no reason why industry should want to replace wood, brick, concrete, and metals when the latter are adequate and inexpensive. Too much has been written about the coming "Plastics and Light Metal Age," which is prophesized as the successor to the Stone Age, the Bronze Age, and the Iron Age. In the historical sequence of these earlier periods, there is logic in the quantitative sense; one age gave way to another when the use of a new material exceeded in quantity that of its predecessor. For the plastics and light metals, however, a different picture presents itself; less than 3,000,000 tons of all these materials are being produced annually, while steel production exceeded 90,000,000 tons last year and will probably not recede to less than 60,000,000 tons for many years. This is still the Iron Age or rather the Steel Age. [br] The title that best expresses the idea of this passage is _________.

选项 A、New Uses for Plastics
B、How One Age Succeeds Another.
C、Advantages of Plastics
D、Limitations on the Use of Plastics

答案 D

解析 A项,C项很容易先排除,B项容易混淆,但文章内容主要讨论的不是时代变迁,而是论证塑料的局限性,它不是这个时代的标志物质。所以选择D项才是正确的。
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