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
2023-11-23
30
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 burns 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200,000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/3211189.html
相关试题推荐
Then,whydoAmericanswanttoworkharder?Onereasonmaybethatthereal
Then,whydoAmericanswanttoworkharder?Onereasonmaybethatthereal
Then,whydoAmericanswanttoworkharder?Onereasonmaybethatthereal
Then,whydoAmericanswanttoworkharder?Onereasonmaybethatthereal
Then,whydoAmericanswanttoworkharder?Onereasonmaybethatthereal
Then,whydoAmericanswanttoworkharder?Onereasonmaybethatthereal
Womenfromthemid-30stothemid-50sarelesslikelythanAmericansoverall
Womenfromthemid-30stothemid-50sarelesslikelythanAmericansoverall
Womenfromthemid-30stothemid-50sarelesslikelythanAmericansoverall
Womenfromthemid-30stothemid-50sarelesslikelythanAmericansoverall
随机试题
【B1】[br]【B6】[audioFiles]audio_eusm_j01_084(20099)[/audioFiles]gradually此处是说通过
[已过时]下列关于专用通气管的作用的叙述中,哪几项不正确?( )A.专用通气立
新生儿肺炎早期最主要的临床特点是A.发热伴剧咳 B.气急伴鼻翼翕动 C.肺部
教学环境包括物质环境和{}。
小建中汤原方中芍药与桂枝的用量比例为A.4:1B.3:1C.2:1D.5:1E.
下列关于体温的叙述,错误的是A、是指机体深部的平均温度 B、腋窝温度>直肠温度
链霉素过敏反应时,使用葡萄糖酸钙的目的是A:维持血压 B:解除支气管痉挛 C
认知因素致病的原因不包括()。 (A)对逻辑的推理出现失误(B)对事物的
下列水资源利用评价相关指标中,反映用水效率和效益的指标有( )。【新教材已删除
某分部工程有4个施工过程,各分为3个施工段组织加快的成倍节拍流水施工。各施工过程
最新回复
(
0
)