byHannahSperberNarrativeNonfictionPlanetPOWERNarrativeNonfictionPAIREDREADHeliosandPhaetonNarrativeNonfictionAPhotographyCredit:RobertGlusic/CORBIS**Thetotalwordcountisbasedonwordsintherunningtextandheadingsonly.Numeralsandwordsincaptions,labels,diagrams,charts,andsidebarsarenotincluded.STRATEGIES&SKILLSWordCount:1,154**ComprehensionStrategy:AskandAnswerQuestionsSkill:MainIdeaandKeyDetailsVocabularyStrategyLatinandGreekPrefixesVocabularycoincidence,consequences,consume,converted,efficient,incredible,installed,renewableContentStandardsScienceEarthScienceCopyright©TheMcGraw-HillCompanies,Inc.Allrightsreserved.Nopartofthispublicationmaybereproducedordistributedinanyformorbyanymeans,orstoredinadatabaseorretrievalsystem,withoutthepriorwrittenconsentofTheMcGraw-HillCompanies,Inc.,including,butnotlimitedto,networkstorageortransmission,orbroadcastfordistancelearning.Sendallinquiriesto:McGraw-HillEducationTwoPennPlazaNewYork,NewYork10121ISBN:978-0-02-119130-7MHID:0-02-119130-1PrintedintheUnitedStates.123456789QLM151413121110PAIREDREADEssentialQuestionHowhaveourenergyresourceschangedovertheyears?Introduction.............................2Chapter1ThePowerofWater.....................4Chapter2HeatfromtheInside.....................7Chapter3ThePoweroftheSun..................10Conclusion..............................14RespondtoReading....................15HeliosandPhaeton............16Glossary/Index..........................19FocusonScience...............20byHannahSperberPlanetPOWERThinkstock/MasterfileIntroductionWeuseenergyforlotsofthings.Weuseittomakelight.Weuseittorunourcomputers.Weuseittomakeheat.Energyisincredible.Mostoftheenergyweconsumetodaycomesfromburningfossilfuels.Oil,gas,andcoalarefossilfuels.Fossilfuelscomefromplantsandanimalsthatlivedmillionsofyearsago.Burningfossilfuelssuchascoalpollutestheair.2LarryLeePhotography/CORBISWindfarmspowermillionsofhomesintheUnitedStates.Burningfossilfuelspollutestheair.Fossilfuelscanonlybeusedonce.Thismeansthattheyarenotrenewable.One...
