精选优质文档-倾情为你奉上in the above graph, we can see it clearly that.Im impressed by the graph.ItisobviousinthegraphthattherateofAhasundergonedramaticchanges.Ithasgoneup/droppedconsiderablyinrecentyears.AtthepointofX,Areachesitspeakvalueof.on seeing this picture, I cant help remembering in our life there are such people indeed.Whatisthereasonforthischange?Mainlytherearesomereasonsbehindthesituationreflectedinthegraph.Firstofall,