首页
登录
职称英语
As the cost of gas and oil for home heating has gone up, many Americans hav
As the cost of gas and oil for home heating has gone up, many Americans hav
游客
2024-10-09
44
管理
问题
As the cost of gas and oil for home heating has gone up, many Americans have switched from these fuels to wood for heating their homes. In 1973, approximately 200,000 wood-burning stoves, intended for home use, were sold in the United States; by 1979, this figure had reached one million; and by the end of 1981, there were as many as seven million home owned wood-burning units in operation in the U. S.
In addition to low fuel bills, many people choose these stoves because their initial cost is very low (the prices range from $ 50 kits to $ 5,000 top-of-the-line models), and because new technology has made wood fires more efficient, cleaner, and, therefore, safer than ever before.
One new technological feature of this type is the catalytic(催化) combustor which adds about $ 100 to $ 200 to the cost of the stove, but which causes much more complete combustion (燃烧) of the wood and therefore bums up more of the pollutants left by incomplete combustion and produces more heat.
A second cost-saving innovation is a device which agitates the wood, increasing the amount of oxygen that reaches the center of the wood pile, and leading to more efficient combustion. The real advantage of this device is that it allows the owner to make use of cheap sources of wood such as dirty wood chips (an industrial by-product) that have almost no commercial value, cost as little as $ 20 a ton, and burn very inefficiently in furnaces without an agitator. [br] According to the passage, the number of wood-burning stove sold for home use ______.
选项
A、went up fivefold over a six-year period
B、rose to seven million during the seventies
C、multiplied thirty-five times between 1973 and the beginning of 1981
D、increased by 6,000,000 over an eight-year period
答案
A
解析
文中第一段说1973年有20万燃木家用取暖炉出售了;到1979年,此数字达到一百万;到1981年末,此数字达到了七百万。因此对照后,A项正确。
转载请注明原文地址:https://tihaiku.com/zcyy/3793417.html
相关试题推荐
Americansoftensaythatthereareonlytwothingsapersoncanbesureofi
Americansoftensaythatthereareonlytwothingsapersoncanbesureofi
Americansoftensaythatthereareonlytwothingsapersoncanbesureofi
Americansoftensaythatthereareonlytwothingsapersoncanbesureofi
YoungerAmericanswillhavetotakeourwordforit;therewasatime,wayb
YoungerAmericanswillhavetotakeourwordforit;therewasatime,wayb
MillionsofAmericansruntothebankorvisitautomatedtellermachineswh
Asthecostofgasandoilforhomeheatinghasgoneup,manyAmericanshav
Asthecostofgasandoilforhomeheatinghasgoneup,manyAmericanshav
Myfatherissodeafthathehastouseaheating______.A、helpB、aidC、support
随机试题
【S1】[br]【S10】very→much/去掉very
Becauseofthe______ofitsideas,thebookwasinwidecirculationbothathom
Tonyisverydisappointed______theresultsoftheexam.A、towardB、withC、onD、
Occasionalself-medicationhasalwaysbeenpartofnormalliving.Themaking
试结合实际说明应该如何帮助学生有效地管理学习时间。
某加工厂,一台卧式土锅炉在运行时发生爆炸,死亡三人,受伤三人,直接经济损失300
罗女士,30岁。3天来发热、咳嗽,极度乏力,全身皮肤广泛点片状出血,急诊入院。实
结构比闸阀简单,制造、维修方便,也可以调节流量,应用广泛。流动阻力大,为防止堵塞
霍乱患者肌肉痉挛主要是由于A.低钠和电解质丢失 B.高热 C.低钾 D.细
(2011年真题)安全生产许可证的有效期为()年A.1 B.2 C.3
最新回复
(
0
)