题目

The reason ______ he failed was _______ he was too careless A. because; because    B. why; because   C. that; that     D. why; that 答案：D 解析: 略灵活选用计算方法．98+99×98　　　　　　 102×36　　　　　　 276+428+124+572375÷（25-10）×15　　 125×43-25×43　　　648÷[（46-37）×4]．