Thefoodweeatseemstohaveprofoundeffectsonourhealth.Althoughsciencehasmadeenormousstepsinmakingfoodmorefittoeat,ithas,atthesametime,mademanyfoodsunfittoeat.Someresearchhasshownthatperhapseightypercentofcancerisrelatedtothedietaswell,especiallycancerthecolon.Differentculturesaremorepronetocontractcertainillnessesbecauseofthefoodthatischaracteristicinthesecultures.Thatfoodrelatedtollnessisnotanewdiscovery.In1945,governmentresearchersrealizedthatitratesandnitrites,commonlyusedtopreservecolorinmeats,andotherfooddditives,causedcancer.Yet,thesecarcinogenicadditivesremaininourfood,nditbecomesmoredifficultallthetimetoknowwhichthingsonthepackginglabelsofprocessedfoodarehelpfulorharmful.Theadditiveswhichweeatarenotallsodirect.Farmersoftengivepenicillintobeefandpoultry,andbecauseofthis,penicillinhasbeenfoundinthemilkoftreatedcows.Sometimessimilardrugsareadministeredtoanimalsnotformedicinalpurposes,butforfinancialreasons.Thefarmersaresimplytryingtofattentheanimalsinordertoobtainahigherpriceonthemarket.AlthoughtheFoodandDrugAdministration(FDA)hastriedrepeatedlytocontroltheseprocedures,thepracticescontinue.
48.Whatisthemaintopicofthepassage?
A.Foodandourhealth
BFoodandadditives
C.Foodandcancer
DFoodandculture
49AllofthefollowingstatementsaretrueEXCEPT_______.
AFortypercentofcanceriscausedbyproblemsrelatedtofood.
BResearchershaveknownaboutthepotentialdangeroffoodadditivesformanyyears
C.Weeatsomeofthefoodadditivesdirectlyandsomeindirectly
DDrugsarealwaysgiventoanimalsformedicinalpurposes
50.Whydofarmersgivedrugstotheiranimals?
A.tospeedupthegrowthofanimals
BTomaketheanimalsfatter
Ctomaketheanimals’meatfittoeat
DTomaketheanimals’meatrichinnutrients
51.Itcanbeinferredfromthepassagethat_________.
Ascientisthavemadeallthefoodfittoeat
Bonlyinrecentyearshavepeoplefoundthatthefoodisrelatedtoone’sillness
Callkindsofcancerarerelatedtothediet
Dsomeadditivesareharmfultoourhealth
52.Theword“this”inthesecondsentenceofparagraph2mostprobablyrefersto__________.
Afarmer
Bpenicillin
Cbeefandpoultry
Dthefactthatfarmersoftengivepenicillintoabeef
下列哪種格式不支持剪貼路徑：
若想增加一個圖層，但在圖層調色板的最下面NEWLAYER（創建新圖層）的按鈕是灰色不可選，原因是下列選項種的哪一個（假設圖象是8位/通道）（）
混凝土耐久性主要包括()等幾個方面。
要刪除所有打開的圖象文件的歷史記錄，應采用下列哪個命令：
