首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
专升本
When aluminum was first produced about a hundred and fifty years ago, it was so difficult to separate from the ores in which it
When aluminum was first produced about a hundred and fifty years ago, it was so difficult to separate from the ores in which it
admin
2009-08-21
55
问题
When aluminum was first produced about a hundred and fifty years ago, it was so difficult to separate from the ores in which it was found that its price was higher than that of gold. The price remained high until a new process was discovered for refining the metal with the aid of electricity approximately three quarters of a century later. The new method was so much cheaper that aluminum became practical for many purposes, one of which was making pots and pans.
Aluminum is lightweight, rustproof and easily shaped into different forms. By mixing it with other metals, scientists have been able to produce a variety of alloys, some of which have the strength of steel but weigh only one third as much.
Today, the uses of aluminum are innumerable. Perhaps its most important use is in transportation. Aluminum is found in the engine of automobiles, in the hulls of boats. It is also used in many parts of airplanes. In fact, the huge "airbus" planes would probably never have been produced if aluminum did not exist. By making vehicles lighter in weight aluminum has greatly reduced the amount of fuel needed to move them. Aluminum is also being used extensively in the building industry in some countries.
Since aluminum is such a versatile(多用的) metal, it is fortunate that bauxite(铝土矿), which is one of its chief sources, is also one of the earth’s most plentiful substances. As the source of aluminum is almost inexhaustible, we can expect that more and more uses will be found for this versatile metal.
选项
A、wind
B、solar energy
C、hydraulic power
D、electricity
答案
D
解析
本题为客观细节题。从文中第一段最后两句“The price remained high until a new process was discovered for refining the metal with the aid of electricity approximately three quarters of a century later.The new method was so much cheaper...”中可以得知选项D是正确答案。
转载请注明原文地址:https://kaotiyun.com/show/GfSC777K
本试题收录于:
英语题库成考专升本分类
0
英语
成考专升本
相关试题推荐
Forthispart,youaresupposedtowritealetterof100-120wordsbasedonthefollowingsituation.Remembertowriteitclearl
Somepeoplethinkthemoreexpensiveaproductis,thebetteritwillbe.(但事实并非如此).
Accordingtothepassage,thecomingofonlinejobsearchingbrings______.ProfessorChallengerthinks______.shouldbeconsid
Ifproductfails,thecustomerswillprobablyselectanotherproductandmaybecome______angryatthemanufacturerthattheyn
Allthevillagersreturnedhome______thatthedangerwasover.
Whenyouaremakingaspeech,alwaysremembertokeepitshortand______.
Childrenwhoareoverprotectedbytheirparentsmaybecome______.
Itisimportantthatyoucontactthemwhenyoufirstbecomeawareaproblemmightbedevelopingratherthanwaitinguntilithas
随机试题
防腐蚀涂料成膜物质大多数是()。
下述造影目前已基本淘汰,除了
A.丙酸倍氯米松B.沙美特罗C.异丙托溴铵D.扎鲁司特E.茶碱分子内有莨菪碱结构()。
死亡的3阶段是
给水附件用以控制调节系统内水的(),保证系统运行安全。
在现有开放式基金销售过程中,商业银行不仅提供了完善的硬件设施和客户群,也提供了满足投资者需求的个性化服务。()
下列关于内部研发无形资产的会计处理的说法中,错误的是()。
在平行结转分步法下,只计算()。
大学生利用假期当保姆已不再是新鲜事。一项调查显示,63%的被调查者赞成大学生当保姆,但是,当问到自己家里是否会请大学生保姆时,却有近60%的人表示“不会”。以下哪项陈述如果为真,能够合理地解释上述看似矛盾的现象?()
设f(x)在[0,1]连续,f(|cosx|)dx=A,则I=f(|cosx|)dx=__________.
最新回复
(
0
)