阅读理解TheaveragecollegestudentsinAmericaspentanestimated（...
问题详情：阅读理解TheaveragecollegestudentsinAmericaspentanestimated（结算的）$700ontextbookslastyear．TheNationalAssociationofCollegeStoresreportedmorethan$5billioninsalesoftextbooksandcoursematerials（课程资...