Didyouknowthatthenoiseinyourschoolyardcanharmyourhearingseriously?Duringbreaksatschool,youfindyourselfinthemiddleofloudactivitiesinthehallwaysandtheschoolyard.Youneedbreakstohavefunwithyourfriends,butyoushouldbecarefulasthenoiseatschoolcanbedangeroustoyourhearing.Herearesomeexamplesofschoolyardnoise:･Climbingthejunglegym(atadistanceof25meters):70-100dB(分贝);･Girlshouting(atadistanceof3meters):120dB;･Boyshouting(atadistanceof3meters):I20-130dB;･Studentsthrowingashovel(铁铲)onawoodenbox(atadistanceof1meter):135dBSomefactors(因素)decidehowharmfulanoiseistothehumanear:thedistancetothenoise,thelevelofthenoiseandthetimeitlasts.Wecanstandnoiseatthelevelof85dBforeighthoursaday.Butasthenoiseincreases,wecanonlystandthenoiseforshorterandshorterperiodsoftime.Whenthenoiselevelreaches115dB,ourearscanstanditforlessthan30secondsaday.Noiseatthelevelof130dBharmsyourhearingifyouhearitformorethanonesinglesecondaday.Ifyouwanttoenjoyyourbreaks,youshouldhelpkeepingthenoiseleveldown.1.Fromthepassage,weknowthat______factorsdecidehowharmfulanoiseistothehumanear.A.twoB.threeC.fourD.five2.Ourhearingwillnotbeharmedbynoise______.A.atthelevelof85dBfor12hoursadayB.atthelevelof115dBfor20secondsadayC.atthelevelof130dBfor5secondsadayD.atthelevelof135dBfor3secondsaday3.Whatisthemainideaofthepassage?A.Noiseatschoolcanreachveryhighlevels.B.Therearemanykindsofnoiseintheschoolyard.C.Studentsshouldn'thaveactivitiesintheschoolyard.D.Noiseatschoolcanbeveryharmfultostudents'hearing.4.Howmanyhourscanwestandnoiseatthelevelof85dBperday?A.fivehoursB.eighthoursC.fourhoursD.onehour（10.0分）
第一空：A第二空：B第三空：D第四空：B
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针具器械高压消毒时，适宜的温度是 A: 100℃～120℃ B: 115℃～123℃ C: 120℃～130℃ D: 125℃～135℃ E: 130℃～140℃
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简答题5汉译日：我给您打过电话，但您那时正好在通话中。（･･･中）
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人耳对1kHZ声波感觉的声强从10-12W/m2到1<br/>W/m2,若用分贝表示,其范围是( ) A: 12~2<br/>dB B: 1~120<br/>dB C: 0~12<br/>dB D: 0~120<br/>dB E: 1~12<br/>d( B )
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It took（）years for world population to grow from 1 billion to 3 billion. A: 100 B: 115 C: 130 D: 145
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He has a room 5 meters long and 3 meters wide________.