Aprofessorwasgivingabigtestonedaytohisstudents.Hehandedoutallofthetestsandwentbacktohisdesktowait.Oncethetestwasoverthestudentsallhandedthetestsbackin.Theprofessornoticedthatoneofthestudentshadattacheda$100billtohistestwithanotesaying"Adollarperpoint."Inthenextclasstheprofessorhandedthetestsbackout.Thisstudentgotbackhistestand$64change.                    
                    
请用微信扫添加公众号