首页
登录
职称英语
After going over some basic about hearing, the teacher will lead the students to
After going over some basic about hearing, the teacher will lead the students to
游客
2023-11-12
28
管理
问题
After going over some basic about hearing, the teacher will lead the students to [br]
I’m glad to see so many of you here. We’ve become really alarmed over the health center by the number of students we are seeing, who are experiencing hearing loss. (17)First, I want to go over some basic about hearing. Then we can take a look at our school environment and see if we can figure out some ways to protect hearing. (18)The leading cause of preventable hearing loss is excessive noise. Too much moderate noise for a long time or some types of intense noise for even a short time can damage hearing. Loudness is measured in units called decibels. One decibel is the lowest sound that the average person can here. (19)Sounds up to 80 decibels generally aren’t harmful. That’s noise like traffic on a busy street. But anything louder than 80 decibels, especially with continuous exposure, may eventually hurt your hearing. (20)Once you are up to around 140 decibels, that’s like a jet plane taking off, then you might even feel pain in your ears. And pain is a sure sign that your hearing’s at risk. Even one exposure to a really loud noise at close range can cause hearing loss. So what you need to do is limit your exposure to harmful levels. If you pass along this handout, we can take a look at the decibel level of some common campus sounds. Notice how loud those horns are that people take to football games. They are really dangerous if blown right behind you. Now, let’s try to generate a list of damaging noises.
选项
A、excessive noise
B、too much moderate noise for a long time
C、intense noise for even a short time
D、moderate noise for a short time
答案
D
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3181727.html
相关试题推荐
Nowadays,mostcollegesanduniversitiesencouragestudentsto[br][originalte
Nowadays,mostcollegesanduniversitiesencouragestudentsto[originaltext]
Ofthefourgroupsofstudents,whoscoredthelowestinmathsaccordingtothe
Ofthefourgroupsofstudents,whoscoredthelowestinmathsaccordingtothe
Tomysurprise,themajorityofthestudents_____infavorofhisproposal.A、isB
Thestudentsexpectedthere______morereviewingclassesbeforethefinalexams.A
Theairlineschargehalf-priceforthestudents._____,I’vealreadyboughtmyti
Itwasunusualforthere______sofewstudentsintheclassroom.A、tobeB、beC、
Allhisteachers______hissuccesstohisdiligenceandperseverance.A、oweB、re
Thetuitionfeesare______tostudentscomingfromlow-incomefamilies.A、approac
随机试题
HismannerwassopleasantthatBollafeltat______withhimatonce.A、peaceB、
[originaltext]Asstrugglingairlinesaddextra-luggagefeesandtravelerswo
烧伤包括()。A.烫伤 B.热烧伤 C.电烧伤 D.火烧伤 E.化学烧
A.黄芪、沙参、百合 B.桂枝、白芍、制附片 C.桃仁、苏木 D.黄芩、前
氨基苷类抗生素的抗菌机制是A.影响叶酸代谢B.影响胞浆膜的通透性C.抑制细菌细胞
A.该反应的正反应是吸热反应 B.该反应的逆反应是放热反应 C.该反应的正反
为减少路基工后沉降,对高路堤拓宽部分的地基不宜单独采用()措施。A.换填砂石
总承包项目在试运行和交付的试车中,不符合考核验收原则的是( )。A.考核指标应为
槽式光热发电设备的驱动装置旋转角度宜为( )。 A.±90° B.±360
最新回复
(
0
)