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
A、By sending water directly back to the sea with great force. B、By reducing wave energy. C、By reducing beach width. D、By stabili
A、By sending water directly back to the sea with great force. B、By reducing wave energy. C、By reducing beach width. D、By stabili
admin
2009-04-23
29
问题
Your professor has asked me to talk to you today about the topic that should be of real concern to civil engineers: the erosion of the US beaches. Let me start with some statistics, Did you know that 90% of the coast in this country is eroding, on the gulf of Mexico for instance, erosion averages 4 to 5 feet per year? Over the past 20 years, there has been an increase in building along the coast, even though geologists and environmentalists have been warning communities about problems like erosion. Someway, communities have tried to protect their buildings and roads and to build seawalls. However, geologists have found that such stabilizing structures actually speed up the destruction of the beaches. These beaches with seawalls, called stabilized beaches, are much narrower than beaches without them. You may wonder how seawalls speed up beach loss. The explanation is simple. If the flow of the beaches is gentle, the water energy is lessened as it washes up along the shore. It is reduced even more that returns to the sea so it doesn’t carry back much sand. On the other hand, when the water hits the nearly vertical face of the seawall, it goes straight back to the sea with the full force of its energy and it carries back a great deal of sand. Because of the real risk of losing beaches, many geologists support a ban on all types of stabilizing construction on shorelines.
选项
A、By sending water directly back to the sea with great force.
B、By reducing wave energy.
C、By reducing beach width.
D、By stabilizing beachfront construction.
答案
B
解析
How does a gently sloping beach help prevent erosion?
转载请注明原文地址:https://kaotiyun.com/show/bqZK777K
0
大学英语六级
相关试题推荐
Therewasanearthquakehappened,______100peopleandwithmorethan300______.
AbouthowmanyadultAmericanshavethe"weightproblem"?______percent.
Theyregard______astheirdutytoprovidethebestservicefortheircustomers.
Whenyoubuylifeinsurance,youwantapolicythatfitsyourneedsatareasonablecost.Yourfirststepistodeterminehowmu
LadiesandGentlemen,WelcometoLondonInternationalLanguageCenter.WeteachEnglishforboth【T1】______andbusinesspurpo
Oneyearagotoday,youngJim’sparentshadaveryserioustalkwithhim.Theycomplainedthathehadspentalotoftimebefore
A、Writehisworkreport.B、Goshoppingwiththewoman.C、Shopaloneforashirt.D、Dosomethingtorelax.A女士问周六一起去逛街怎么样,男士说他倒是想
Wehaveestablishedanonlinecommunicationsystemwithdealersinordertoserveourcustomersinthebestwaywecan.
Theseproductscertainlydonotmatchthesamplesyouhavesentus.andneitheraretheysuitedtotheneedsofourcustomers.
CertainphrasesonecommonlyhearsamongAmericanscapturetheirdevotiontoindividualism:"Doyourownthing.""Ididitmywa
随机试题
φoCu2+/Cu+=0.17V,φoI2/I-=0.535V,因此Cu2+离子不能氧化I-离子。()
患者,女,26岁。产后4周出现体温升高、右侧乳房疼痛、局部红肿、有波动感,最主要护理措施是()。
通常负责分派病案号码的部门是
有头疽初起症状多见
根据《中华人民共和国行政诉讼法》的规定,公民、法人或者其他组织对()事项提起的诉讼,人民法院不予受理。
氽业发生的废品损失,应计入营业外支出。()
下列关于窗体的描述中,错误的是()。
HowtoapproachReadingTestPartOne•InthispartoftheReadingTestyoumatchsevenstatementswithfourshorttexts.•Fir
Everyyeartelevisionstationsreceivehundredsofcomplaintsabouttheloudnessofadvertisements.However,federalrulesforb
Hemusthavegonetothecinemalastnight,______?
最新回复
(
0
)