现要配制pH=4.5的缓冲溶液，最理想的缓冲对是 ()

已知HAc的pKa=4.75，当溶液的pH=7.25时溶液中的主要型体是（）

已知NH3·H2O的pKb=4.74，计算0.10mol∙L-1NH4Cl溶液的pH（）

将以下数修约为4位有效数字正确的是（）

4．通过Post方法提交数据，会将所有数据显示在URL地址的后面。（）

4.不能在不同用户之间共享数据的方法是（）（A）通过cookie（B）利用文件系统（C）利用数据库（D）通过ServletContext对象

一个HTML文件中只能有（）个body标签。A、1B、2C、3D、4

使用以下的HTML代码实现的页面效果为下列图表中的（）。<inputname="gen"type="radio"vlaue="male"checked="checked">男<inputname="gen"type="radio"vlaue="female">女<inputname="gen1"type="checkbox"vlaue="male"checked="checked">男<inputname="gen2"type="checkbox"vlaue="female">女A.图1B.图2C.图D.图4

下列审计程序中，既可以用于风险评估程序，又可以用于控制测试的有（　　）。

4．母は背が高いですが、父（　）低いです。

4.ThenationalflagofthePeople'sRepublicofChinaisredincolor,rectangularinshape,withfivestars.

对（）等账户余额进行实质性测试，应当在采购与付款循环审计中进行。

测试现金余额的起点是核对现金日记账与总账的余额是否相符（）。

对各类交易、账户余额、列报的具体细节进行的测试称为（）。

Althoughmanyofusmayfeelair-conditionersbringrelieffromhot,humidorpollutedoutsideair,theyposemanypotentialhealthhazards.Muchresearchhaslookedathowthemovementofairinsideaclosedenvironment---suchasanofficebuilding---canspreaddiseaseorexposepeopleinthebuildingtoharmfulchemicals.OneofthemorewidelypublicizeddangersisthatofLegionnaire’sdisease,whichwasfirstrecognizedinthe1970s.Thiswasfoundtohaveaffectedpeopleinbuildingswithair-conditioningsystemsinwhichwarmairpumpedoutofthesystem’coolingtowerswassomehowsuckedbackintotheairintake(通风口),inmostcasesduetopoordesign.Thewarmair,filledwithbacteria,wascombinedwithcooled,conditionedairandwasthencirculatedaroundvariouspartsofthebuilding.Studiesshowedthatevenpeopleoutsidesuchbuildingswereatriskiftheywalkedpastairexhaustpipes.Largeair-conditioningsystemsaddwatertotheairtheycirculatebymeansofhumidifiers(湿度调节器).Inoldersystems,thewaterusedforthisprocessiskeptinspecialreservoirs,thebottomsofwhichprovidebreedinggroundsforbacteriawhichcanfindtheirwayintotheventilation(通风)system.Therisktohumanhealthfromthissituationhasbeenhighlightedbythefactthattheimmunesystems(免疫系统)ofapproximatelyhalfofworkersinair-conditionedofficebuildingshavedevelopedtheabilitytofightofftheorganismsfoundatthebottomofsystemreservoirs.Butchemicalscalled“biocides”areaddedtoreservoirstomakethemgerm-free,andtheyaredangerousintheirownrightinsufficientquantities,astheyoftencontaincompoundsstronglylinkedtocancers.Finally,itshouldbepointedoutthattheartificialclimaticenvironmentcreatedbyair-conditionerscanalsoaffectus.Inanaturalenvironment,whetherindoororoutdoor,therearesmallvariationsintemperatureandhumidity.Indeed,thehumanbodyhaslongbeenaccustomedtothesenormalchanges.Inanair-conditionedlivingorworkingenvironment,however,bodytemperaturesremainwellunder37℃,ournormaltemperature.Thisleadstoaweakenedimmunesystemandthusgreaterexposuretodiseasessuchascoldsandflu.4.Theauthormostprobablywantsthereaderstotreatbiocideswithanattitudeof_.