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
31
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、140 decibels
B、100 decibels
C、80 decibels
D、60 decibels
答案
C
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3181728.html
相关试题推荐
ManyforeignstudentscometostudyintheU.S.,some______byscholarships,othe
Ph.Dstudentswhohaven’tcompletedtheirdissertationsbythetimetheirfellow
Theteacheraskedaverydifficultquestion,butfinallyTed_____asatisfactory
ItispossibleforstudentstoobtainadvanceddegreeinEnglishwhileknow
ItispossibleforstudentstoobtainadvanceddegreeinEnglishwhileknow
Shewastrying______bytheteacherinclass.A、avoidingquestioningB、avoidingt
Itisimperativethatthestudents______tohandintheirpapersontime.A、to
Thestudentsinthedormitorieswereforbidden,unlesstheyhadspecialpassed,
WhatisthetotalnumberofstudentsatDeepSpringCollege?[br][originaltext
WhatisthetotalnumberofstudentsatDeepSpringCollege?[originaltext]
随机试题
[originaltext]W:IsMaryreadytogototheairport?M:Ready?Shehasn’tevenfi
C各项重新变形后,底数为5X1,5X11,5X11X11,5X11X11X11,所以下一项应为5X11X11X11X11,即为C。
妊娠3~5个月胚胎期的主要造血器官是()A.肝 B.脾 C.胸腺
下方分别是一个由长方体堆积而成的立体图形和该立体图形的左视图、后视图,那么该立体
迎香穴位于A.鼻孔外缘,旁开0.5寸 B.鼻翼外缘,旁开0.5寸 C.
A.出血性膀胱炎B.肾脏毒性C.心脏毒性D.过敏反应E.乙酰胆碱综合征环磷酰胺
假定风荷载沿高度呈倒三角形分布,地面处为0,屋顶处风荷载设计值q=134.7kN
(2017年5月)()的首要工作是组织好部门员工实施项目任务和协调上下
(2018年真题)假设其他条件不变,我国东北灾害性天气的出现,将对()期货
甲股份公司共有股权1000万股,为了将来有更好的发展,将80%的股权让乙公司收购
最新回复
(
0
)