PassageFourQuestions16to20arebasedonthefollowingpassage.ProfessorAshokGoelofGeorgiaTechdevelopedanartificiallyintelligentteachingassistanttohelphandletheenormousnumberofstudentquestionsintheonlineclass,Knowledge-BasedArtificialIntelligence.ThisonlinecourseisacorerequirementofGeorgiaTech’sonlineMasterofScienceinComputerScienceprogram.ProfessorGoelalreadyhadeightteachingassistants,butthatwasn’tenoughtodealwiththeoverwhelmingnumberofdailyquestionsfromstudents.Manystudentsdropoutofonlinecoursesbecauseofthelackofteachingsupport.Whenstudentsfeelisolatedorconfusedandreachoutwithquestionsthatgounanswered,theirmotivationtocontinuebeginstofade.ProfessorGoeldecidedtodosomethingtoremedythissituationandhissolutionwastocreateavirtualassistantnamedJillWatson,whichisbasedontheIBMWatsonplatform.GoelandhisteamdevelopedseveralversionsofJillWatsonbeforereleasinghertotheonlineforums.Atfirst,thevirtualassistantwasn’ttoogreat.ButGoelandhisteamsourcedtheonlinediscussionforumtofindallthe40,000questionsthathadeverbeenaskedsincetheclasswaslaunched.ThentheybegantofeedJillwiththequestionsandanswers.Aftersomeadjustmentsandsufficienttime,Jillwasabletoanswerthestudents’questionscorrectly97%ofthetime.Thevirtualassistantbecamesoadvancedandrealisticthatthestudentsdidn’tknowshewasacomputer.Thestudents,whowerestudyingartificialintelligence,wereinteractingwiththevirtualassistantandcouldn’ttellitapartfromarealhumanbeing.Goeldidn’tinformthemaboutJill’strueidentityuntilApril26.Thestudentswereactuallyverypositiveabouttheexperience.ThegoalofProfessorGoel’svirtualassistantnextyearistotakeoveranswering40%ofallthequestionsposedbystudentsontheonlineforum.ThenameJillWatsonwill,ofcourse,changetosomethingelsenextsemester.ProfessorGoelhasamuchrosieroutlookonthefutureofartificialintelligencethan,say,ElonMusk,StephenHawking,BillGatesorSteveWozniak.16.WhatdowelearnaboutKnowledge-BasedArtificialIntelligence?