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
外语
Municipal sewage is of relative]y recent origin as a pollutant. It was first brought to public attention in the 19th century by
Municipal sewage is of relative]y recent origin as a pollutant. It was first brought to public attention in the 19th century by
admin
2010-02-17
45
问题
Municipal sewage is of relative]y recent origin as a pollutant. It was first brought to public attention in the 19th century by a London physician who showed that the city’s cholera outbreak had been caused by just one contaminated well. Even though the contamination of drinking water by disease germs has been nearly eliminated in this country, hundreds of communities are still discharging raw sewage into streams and rivers.
When we consider that this sewage contains effluents from toilets, hospitals, laundries, industrial plants, etc. , then the potential of the pollutants as a health hazard is apparent.
The problem of municipal sewage disposal is complicated by the fact that, years ago, most cities combined their storm and waste disposal sewers. Many of these combined systems work well, but others cannot cope with sudden heavy rains. When such storms occur, water mixed with sewage may flood and disable treatment plants unless bypassed, untreated, into a stream. In either case; the people may have little protection for several days from these wastes that may contain disease germs.
Even if adequately treated to eliminate the health hazard, sewage is aesthetically undesirable because of odors and colors produced. Detergents have posed a particular disposal problem. Although there is no indication that they are injurious to health, they can cause foaming, which can clog treatment plants and, at the least, spoil the scenic beauty of streams.
Rural and suburban residents should be aware that septic tanks and cesspools are a potential source of pollution to ground water supplies. This is especially true in the suburban areas with a high population density and with
no municipal sewage disposal and treatment system available. In some areas, sewage disposal is accomplished by cesspools. Soil research is furnishing guidelines for more effective and safer use of systems such as these.
The author mentions the London cholera epidemic to ______.
选项
A、prove that the city refused to deal with pollution
B、prove that medical science once knew little about pollution
C、introduce the idea of contaminated water supplies
D、recall a historical fact
答案
C
解析
此题为细节题。答案在第一段。线索词为“London cholera”。此题考查作者引用的目的。A项与文中所述事实相反。B项文中未涉及此话题。D项“London cholera”是一个“historical fact”,却不是作者引用之目的。
转载请注明原文地址:https://kaotiyun.com/show/dI9K777K
0
专业英语四级
相关试题推荐
Asabiglawfirm,WeirFouldsLLP-Barristers&Solicitorsboastsquiteanumberofoutstanding______.
Theyinsistedon______asequals.
Americancitiesare【C1】______otherdriesaroundtheworld.Ineverycountry,citiesreflectthe【C2】______oftheculture.Citi
WriteonANSWERSHEETTWOanote9fabout50-60wordsbasedonthefollowingsituation:YourneighborKate’ssoundsystemi
Ascientificdiscoveryisoftenmade【C1】______beforesomeoneisabletoputittouse.【C2】______,scientistsdiscoveredhowto
Asinglestatusmayhavemultiplerolesattachedtoit,constitutingaroleset.Considerthestatusofapatientinahospital.
Justover10yearsago,IngmarBergmanannouncedthatthewidelyacclaimedFannyandAlexanderwouldmarkhi,lasthurrahasaf
Theauthor______hisnewly-writtenbooktohisparents.
Ican’tfindJennyeverywhere.Where______shebe?
ToliveintheUnitedStatestodayistogainanappreciationforDahrendorf’sassertionthatsocialchangeexistseverywhere.T
随机试题
对于金属晶体来说,增加位错密度或降低位错密度都能增加金属的强度。
存货业务会计制度设计的目标有
24岁,孕2产0,孕24周时超声检查提示:胎盘位于子宫前壁下段,部分覆盖宫颈内口,产科检查正常。该孕妇于37周时突然阴道多量出血,无腹痛,急诊入院。查体:血压90/60mmHg,脉搏100次/分,宫高33cm,胎心140次/分,ROA,头浮,无宫缩,阴
患者女,47岁。慢性支气管炎病史5年,因进食时异物落入右支气管入院。慢性支气管炎的临床表现为
毒蛇咬伤后结扎的最佳时机是
某企业年末损益类账户转账前的本期发生额资料如下:该企业适用的所得税税率为25%。要求:根据上述资料,回答下列问题。根据以上资料,计算利润表中“营业利润”的填列数为()元。
对于伪造学历、会计从业资格证书和资历证明,或者在考试期间违纪行为的,由会计专业技术资格考试管理机构吊销其会计专业技术资格,由发证机关收回其会计专业技术资格证书,()内不得再参加会计专业技术资格考试。
一、注意事项1.申论考试是对应考者阅读理解能力、综合分析能力、提出和解决问题能力、文字表达能力的测试。2.作答参考时限:阅读资料40分钟,作答110分钟。3.仔细阅读给定资料,按照后面提出的“作答要求”作答。二、给定资料1
设u=u(x,y),v=v(x,y)有连续的一阶偏导数且满足条件:F(u,v)=0,其中F有连续的偏导数且
1 Aboutthetimethatschoolsandothersquitereasonablybecameinterestedinseeingtoitthatallchildren,whatevertheirb
最新回复
(
0
)