题目

阅读理解There exist a number of advantages of wearingschool uniforms. The idea may seem disagreeable at first, but considering allthe positive effects coming from wearing uniforms you would be more likely toenjoy them.Teachers love school uniforms because it helpsprovide an orderly learning environment. Having students dressed in uniformsmay teach them how to present themselves in a neat and professional manner. Itgives students the opportunity to learn how to dress like young ladies andgentleman. And they can focus their attention on academics rather than style.Purchasing (购买) schoolu用数学归纳法证明：12-22+32-42+…+（-1）-1•n2=（-1）n-1•n(n+1)2．